Robin E. M. Willems, Stefan C. J. Meskers, Martijn M. Wienk, and René A. J. Janssen

Nat. Photonics 13, 540–546 (2019)

https://www.nature.com/articles/s41566-019-0415-5

Description:

Materials that exhibit thermally activated delayed fluorescence are promising for the realization of efficient organic light-emitting diodes. However, finding suitable deep-blue thermally activated delayed fluorescence materials is still challenging. Here, we report two highly efficient deep-blue thermally activated delayed fluorescence emitters, TDBA–Ac and TDBA–DI, containing oxygen-bridged, symmetric and rigid boron acceptor moieties.

Robin E. M. Willems, Stefan C. J. Meskers, Martijn M. Wienk, and René A. J. Janssen

J. Phys. Chem. C 2019, 123, 16, 10253–10261

https://pubs.acs.org/doi/10.1021/acs.jpcc.9b00568

Description:

Singlet fission in pentacene creates two triplet excitons per absorbed photon. In a solar cell, each triplet can generate an electron–hole pair, and hence, external quantum efficiencies exceeding 100% have been reported for pentacene–fullerene solar cells. The energetics of this process are intriguing because the minimum photon energy loss, defined as the energy difference between the (triplet) exciton state and the open-circuit voltage, is less than 0.5 eV and distinctively smaller than that in most organic donor–acceptor solar cells. To investigate the energetics of this process, we analyze the effect of the energy of the lowest unoccupied molecular orbital (LUMO) for different fullerene derivatives..

Dimitrios Kourkoulos, Christoph Patron, Thorsten Erich Umbach,

Anne Manuela Umbach, and Klaus Meerholz

Physica Status Solidi (a) May 2020, 1900593

https://doi.org/10.1002/pssa.201900593

Description:

Limited outcoupling efficiencies are still a big problem in organic light‐emitting devices (OLEDs). In this contribution, a simple and general approach for enhancing the outcoupling efficiency of OLEDs is presented: by using a three‐step process, including electrospray deposition of a sacrificial material (step i), thin metal‐layer deposition (step ii), and elution of the sacrificial material (step iii), scattering metal structures are fabricated that can be used in cavity OLEDs. The integration into green‐emitting vacuum‐processed OLEDs yields in increased luminous efficiency and external quantum efficiency (EQE) by 30% and 27%, respectively.

Akmaral Seitkhan, Marios Neophytou, Mindaugas Kirkus, Edy Abou-Hamad,

Mohamed Nejib Hedhili, Emre Yengel, Yuliar Firdaus, Hendrik Faber, Yuanbao Lin,

Leonidas Tsetseris, Iain McCulloch, and Thomas D. Anthopoulos

Adv. Funct. Mater December 5, 2019, 1905810

DOI: 10.1002/adfm.201905810

Description:

A simple approach that enables a consistent enhancement of the electron extracting properties of the widely used small‐molecule Phen‐NaDPO and its application in organic solar cells (OSCs) is reported. It is shown that the addition of minute amounts of the inorganic molecule Sn(SCN)2 into Phen‐NaDPO improves both the electron transport and its film‐forming properties. Use of Phen‐NaDPO:Sn(SCN)2 blend as the electron transport layer (ETL) in binary PM6:IT‐4F OSCs leads to a remarkable increase in the cells' power conversion efficiency (PCE) from 12.6% (Phen‐NaDPO) to 13.5% (Phen‐NaDPO:Sn(SCN)2).

Qiwei Xu, Lingju Meng, Kaustubh Sinha, Farsad I. Chowdhury, Jun Hu, Xihua Wang

ACS Photonics 2020, 7, 1297

https://pubs.acs.org/doi/abs/10.1021/acsphotonics.0c00363

Description:

PbS QDs photodetectors with short rise/fall times (0.33 μs), high sensitivity, and EQE exceeding 100% have been presented by the group of Prof. Xihua Wang. The charge mobility and the epsilon of the active layer were obtained by using photo-CELIV, dark-CELIV, and C-V measurements. The transit time is proportional to the thickness, while the capacitance and the RC time delay are inversely proportional.

Yuliar Firdaus, Qiao He, Yuanbao Lin, Ferry Anggoro Ardy Nugroho, Vincent M. Le Corre, Emre Yengel, Ahmed H. Balawi, Akmaral Seitkhan, Frédéric Laquai, Christoph Langhammer, Feng Liu, Martin Heeney and Thomas D. Anthopoulos

Journal of Materials Chemistry A 2020

https://doi.org/10.1039/C9TA11752K

Description:

The authors show a new wide bandgap acceptor which can be applied in tandem solar cells. The authors use Setfos to simulate the single and tandem device layer thicknesses and thus optimize efficiency. Furthermore, they thoroughly characterize the cells using the Paios platform in order to understand the different efficiency among different acceptors.

Thomas Ferschke, Alexander Hofmann, Wolfgang Brütting and Jens Pflaum

ACS Applied Electronic Materials 2020

https://dx.doi.org/10.1021/acsaelm.9b00687

Abstract:

Determining noninvasively the microscopic optoelectronic parameters of molecular assemblies would constitute an important achievement in material as well as in life sciences. In this contribution, we cope with this challenge by utilizing fluorescent tetraphenyldibenzoperiflanthene (DBP) molecules as optically addressable sensors deterministically positioned in N,NŒ-di(1-naphthyl)-N,NŒ-diphenyl-(1,1Œ- biphenyl)-4,4Œ-diamine/tris(8-hydroxyquinolato)aluminum (NPB/Alq3) organic light-emitting diodes (OLEDs) as a model system.

Sandra Jenatsch, Simon Züfle, Balthasar Blülle, and Beat Ruhstaller

Journal of Applied Physics 127, 031102 (2020)

https://doi.org/10.1063/1.5132599

Abstract:

Generally, Organic Light-Emitting Diodes (OLEDs) are characterized in steady-state. Adding electro-optical measurements in frequency and time domain helps to analyze charge carrier and exciton dynamics, and provides deeper insights into the device physics. In their recent publication “Combining steady-state with frequency and time domain data to quantitatively analyze charge transport in organic light-emitting diodes” Dr. Sandra Jenatsch and colleagues present an overview of frequently used measurement techniques and analytical models for OLEDs. The main part of this tutorial explains how to systematically fit the measured OLED characteristics with microscopic device simulations based on a charge drift-diffusion and exciton migration model in 1D. Moreover, the authors analyze the correlation and sensitivity of the determined material parameters and use the obtained device model to understand the limitations of the specific OLED they considered.

Balthasar Blülle, Stéphane Altazin, Bérengère Frouin, Lidia Stepanova, Sandra Jenatsch, Beat Ruhstaller

SID 2019 DIGEST 50, 407 (2019)

https://doi.org/10.1002/sdtp.13285

Abstract:
Quantum dot (QD) enhanced LCDs are among today’s best-inclass displays exhibiting high brightness and large color gamut. In this presentation we focus on the underlying key mechanism of the embedded QD films, the down-conversion of light, and explore the optical characteristics of a state-of-the-art perovskite QD film by measuring its down-converting properties as a function of the viewing angle. The good agreement of the experimental results with simulations of the QD film indicates that computer aided parameter optimization can be key tool for engineering QD displays.

Martin T. Neukom, Andreas Schiller, Simon Züfle, Evelyne Knapp, Jorge Ávila, Daniel Pérez-del-Rey, Chris Dreessen, Kassio P.S. Zanoni, Michele Sessolo, Henk J. Bolink, Beat Ruhstaller

ACS Applied Materials and Interfaces 11, 23320 (2019)

https://pubs.acs.org/doi/10.1021/acsami.9b04991

Abstract:
A variety of experiments on vacuum-deposited methylammonium lead iodide perovskite solar cells are presented, including JV curves with different scan rates, light intensity-dependent open-circuit voltage, impedance spectra, intensitymodulated photocurrent spectra, transient photocurrents, and transient voltage step responses. All these experimental data sets are successfully reproduced by a charge drift-diffusion simulation model incorporating mobile ions and charge traps using a single set of parameters. While previous modeling studies focused on a single experimental technique, we combine steady-state, transient, and frequency-domain simulations and measurements. Our study is an important step toward quantitative simulation of perovskite solar cells, leading to a deeper understanding of the physical effects in these materials. The analysis of the transient current upon voltage turn-on in the dark reveals that the charge injection properties of the interfaces are triggered by the accumulation of mobile ionic defects. We show that the current rise of voltage step experiments allow for conclusions about the recombination at the interface. Whether one or two mobile ionic species are used in the model has only a minor influence on the observed effects. A delayed current rise observed upon reversing the bias from +3 to -3 V in the dark cannot be reproduced yet by our drift-diffusion model. We speculate that a reversible chemical reaction of mobile ions with the contact material may be the cause of this effect, thus requiring a future model extension. A parameter variation is performed in order to understand the performance-limiting factors of the device under investigation.

Eric A. Margulies, Pierre-Luc T. Boudreault, Vadim I. Adamovich, Bert D. Alleyne, Michael S. Weaver, Julie J. Brown

SID 2019 DIGEST

https://doi.org/10.1002/sdtp.13072

Yong Cui, Huifeng Yao, Jianqi Zhang, Tao Zhang, Yuming Wang, Ling Hong, Kaihu Xian, Bowei Xu, Shaoqing Zhang, Jing Peng, Zhixiang Wei, Feng Gao & Jianhui Hou

Nature Communications 10, 2515 (2019)

https://doi.org/10.1038/s41467-019-10351-5

Markus Regnat, Kurt P. Pernstich, Beat Ruhstaller

Organic Electronics 70, 219-226 (2019)

https://doi.org/10.1016/j.orgel.2019.04.027

Abstract:
We present an electro-optical model of a three-layer phosphorescent OLED which accurately describes the measured current efficiency and transient electroluminescence decay for different biases. Central findings are a bias-dependent emission zone, which influences light outcoupling as well as exciton quenching, and the presence of strong triplet-polaron quenching even at low bias. The measured current efficiency initially increases up to 9 V before it decreases, where the increase is found to be caused by reduced triplet-polaron quenching with holes, while the decrease is caused by a reduced light outcoupling and increased triplet-triplet annihilation. The numerical model allows identifying the individual contributions of the exciton continuity equation and explains the electroluminescence decay, which deviates significantly from a mono-exponential decay due to the dominating influence of exciton generation and quenching after the external bias is removed.

Luiz Gustavo Simão Albano, João Vitor Paulin, Luciana Daniele Trino, Silvia Leticia Fernandes, Carlos Frederico de Oliveira Graeff

Journal of Applied Polymer Science 136, 47805 (2019)

https://dx.doi.org/10.1002/APP.47805

Paramaguru Ganesan, Wen-Yi Hung, Jen-Yung Tso, Chang-Lun Ko, Tsai-Hui Wang, Po-Ting Chen, Hsiu-Fu Hsu, Shih-Hung Liu, Gene-Hsiang Lee, Pi-Tai Chou, Alex K.-Y. Jen and Yun Chi

Advanced Functional Materials 2019, 1900923

https://doi.org/10.1002/adfm.201900923

Jafar I. Khan, Raja S. Ashraf, Maha A. Alamoudi, Mohammed N. Nabi, Hamza N. Mohammed, Andrew Wadsworth, Yuliar Firdaus, Weimin Zhang, Thomas D. Anthopoulos, Iain McCulloch, Frédéric Laquai

Solar RRL (2019)

https://doi.org/10.1002/solr.201900023

Kyungnam Kang and Jungho Kim

Journal of the Korean Physical Society 74, 649 (2019)

https://dx.doi.org/10.3938/jkps.74.649

Rita Rana and Rajesh Mehra

Journal of Electronic Materials (2019)

https://doi.org/10.1007/s11664-019-07221-7

Youqin Zhu, Abay Gadisa, Zhengxing Peng, Masoud Ghasemi, Long Ye, Zheng Xu, Suling Zhao, and Harald Ade

Advanced Energy Materials 1900376 (2019)

https://doi.org/10.1002/aenm.201900376

Shu-Wei Li, Cheng-Hung Yu, Chang-Lun Ko, Tanmay Chatterjee, Wen-Yi Hung and Ken-Tsung Wong

ACS Appl. Mater. Interfaces 2018, 10, 12930−12936

https://doi.org/10.1021/acsami.8b02766

Yuliar Firdaus, Vincent M. Le Corre, Jafar I. Khan, Zhipeng Kan, Frédéric Laquai, Pierre M. Beaujuge, and Thomas D. Anthopoulos

Advanced Science 1802028 (2019)

https://doi.org/10.1002/advs.201802028

Jin-Wook Shin

Dissertation, Tohoku University 2019

http://hdl.handle.net/10097/00125213

Robin E. M. Willems, Stefan C.J. Meskers, Martijn M. Wienk, and René A. J. Janssen

J. Phys. Chem. C (2019)

https://dx.doi.org/10.1021/acs.jpcc.9b00568

Ik Jang Ko, Hyuna Lee, Jin Hwan Park, Gyeong Woo Kim, Raju Lampande, Ramchandra Pode and Jang Hyuk Kwon

Phys. Chem. Chem. Phys. 21, 7083 (2019)

https://doi.org/10.1039/c9cp00965e

Jingyang Xiao, Minrun Ren, Guichuan Zhang, Jianbin Wang, Donglian Zhang, Linlin Liu, Ning Li, Christoph J. Brabec, Hin-Lap Yip and Yong Cao

Solar RRL 201900077 (2019)

https://doi.org/10.1002/solr.201900077

Lieven Penninck, Matthias Diethelm, Stéphane Altazin, Roman Hiestand, Christoph Kirsch, Beat Ruhstaller

Journal of the SID 26, 546 (2018)

https://doi.org/10.1002/jsid.671

Alfian F. Madsuha, Chuyen Van Pham, Michael Eck, Martin Neukom, and Michael Krueger

Journal of Nanomaterials, Article ID 6095863 (2019)

https://doi.org/10.1155/2019/6095863

Zhenchao Li, Ziming Chen, Yongchao Yang, Qifan Xue, Hin-Lap Yip and Yong Cao

Nature Communications 10:1027 (2019)

https://doi.org/10.1038/s41467-019-09011-5

Abstract:

In recent years, substantial progress has been made in developing perovskite light-emitting diodes with near-infrared, red and green emissions and over 20% external quantum efficiency. However, the development of perovskite light-emitting diodes with blue emission remains a great challenge, which retards further development of full-color displays and white-light illumination based on perovskite emissive materials. Here, firstly, through composition and dimensional engineering, we prepare quasi-two-dimensional perovskite thin films with improved blue emission, taking advantages of reduced trap density and enhanced photoluminescence quantum yield. Secondly, we find a vertically non-uniform distribution of perovskite crystals in the PEDOT:PSS/perovskite hybrid film. Through modulating the position of the recombination zone, we activate the majority of quasi-two-dimensional perovskite crystals, and thus demonstrate the most efficient blue perovskite light-emitting diode to date with emission peak at 480 nm, record luminance of 3780 cd m−2 and record external quantum efficiency of 5.7%.

Simon Züfle, Rickard Hansson, Eugene A. Katz, Ellen Moons

Solar Energy 183 (2019) 234–239

https://doi.org/10.1016/j.solener.2019.03.020

https://authors.elsevier.com/c/1YiXX,tRdATFb

Abstract:

Encapsulated organic solar cells often show a burn-in behaviour under illumination. This burn-in manifests itself as a rapid performance loss followed by a much slower progression of the degradation. Here we investigate the burn-in for PCDTBT:PC70BM solar cells under a wide range of illumination intensities. We find that increasing the sunlight concentration from 1 Sun to up to 100 Suns does not change the degradation behaviour, i.e. the dependence of all principal photovoltaic parameters on the dose of solar exposure (in Sun hours). This suggests that the degradation mechanisms under solar concentration (≤100 Suns) are the same as those observed under 1 Sun. This result makes it possible to use concentrated sunlight for accelerated stability assessment of these devices. We also find that devices with PEDOT:PSS as hole transport material show a rapid drop in open-circuit voltage of around 100 mV during the first Sun hour of light exposure. By replacing PEDOT:PSS with MoO3 this initial process can be prevented and only the much slower part of the photo-degradation takes place.

Jelena Vujančević, Pavao Andričević, Anđelika Bjelajac, Veljko Đokić, Maja Popović, Zlatko Rakočević, Endre Horváth, Márton Kollár, Bálint Náfrádi, Andreas Schiller, Kondrad Domanski, László Forró, Vera Pavlović, Đorđe Janaćković

Ceramics International 45,10013 (2019)

https://doi.org/10.1016/j.ceramint.2019.02.045

Abstract:
Highly ordered, anodically grown TiO2 nanotubes on titanium supports were annealed in ammonia atmosphere in order to incorporate nitrogen doping (. 2 at.%) in the titanium oxide lattice. FESEM micrographs revealed nanotubes with an average outer diameter of 101.5 ± 1.5 nm and an average wall thickness of about 13 nm. Anatase crystals were formed inside the tubes after annealing in ammonia atmosphere for 30 min. With further annealing, rutile peaks appeared due to the thermal oxidation of the foil and rise as the duration of heat treatment was increased. The concentration and chemical nature of nitrogen in the nanotube arrays can be correlated to the optical response of dry-pressed heterojunctions of doped TiO2/CH3NH3PbI3 single crystals. The N-TiO2/perovskite heterojunction with the highest amount of interstitial nitrogen exhibited an improved photocurrent, indicating the importance of the semiconductor doping-based heterojunction optimization strategies to deliver competitive levels of halide perovskite-based optoelectronic devices to be envisioned for urban infrastructures.

Dario Di Carlo Rasi, Pieter M. J. G. van Thiel, Haijun Bin, Koen H. Hendriks, Gaël H. L. Heintges, Martijn M. Wienk, Tim Becker, Yongfang Li, Thomas Riedl, and Ren
e A. J. Janssen

Solar RRL 2019, 1800366

https://doi.org/10.1002/solr.201800366

Paramaguru Ganesan, Deng-Gao Chen, Jia-Ling Liao, Wei-Cheng Li, Yi-Ning Lai, Dian Luo, Chih-Hao Chang, Chang-Lun Ko, Wen-Yi Hung, Shun-Wei Liu, Gene-Hsiang Lee, Pi-Tai Chou and Yun Chi

J. Mater Chem. C, 2018, 6, 10088-10100

https://doi.org/10.1039/c8tc03645d

Masaki Tanaka, Hiroki Noda, Hajime Nakanotani, and Chihaya Adachi

Adv. Electron. Mater. 2019, 1800708

https://doi.org/10.1002/aelm.201800708

Abstract:

The relatively short device lifetime of blue organic light‐emitting diodes (OLEDs) when compared with the lifetimes of green and red OLEDs is one of the crucial problems that must be overcome to enable practical application of these devices to full‐color OLED displays. This work focuses on the degradation phenomena of OLEDs that are based on sky‐blue thermally activated delayed fluorescence emitters and clarifies the degradation mechanisms based on spectral change of the electroluminescence, which indicates the formation of electromer emission from an electron transport layer. Additionally, it is determined that the change in the carrier balance that occurs during this degradation process can be ascribed to the formation of electron traps.

Jwo-Huei Jou, You-Ting Lin, Yu-Ting Su, Wei-Chi Song, Shiv Kumar, Deepak Kumar Dubey, Jing-Jong Shyue, Hsun-Yun Chang, Yun-Wen You, Tzu-Wei Liang

Organic Electronics 67 (2019) 222

https://doi.org/10.1016/j.orgel.2019.01.035

Meiyue Liu, Ziming Chen, Zhen Chen, Hin-lap Yip and Yong Cao

Mater. Chem. Front., 2019

https://doi.org/10.1039/C8QM00620B

Abstract:
The tandem architecture for perovskite solar cells has proven successful in promoting the development of such cells. A low-bandgap perovskite solar cell, which typically acts as a back cell, is one of the critical components for tandem perovskite solar cells. However, nowadays, highly efficient low-bandgap perovskite solar cells are mostly based on the inverted structure, which restricts the development of conventional perovskite tandem cells. Therefore, efficient low-bandgap perovskite solar cells based on the conventional structure need to be developed to further extend the availability of device architectures and interfacial materials for tandem cells. Here, by modifying the electron transport materials, we successfully demonstrated an efficient low-bandgap perovskite solar cell based on conventional structure. A ZnO/SnO2/C60-SAM tri-layer was used to engineer the energy level alignment of electron transport layers to reduce the energy loss occurring at the interface and simultaneously suppress the interfacial recombination and improve the charge extraction, resulting in a reduced open-circuit voltage loss for the device. Finally, our low-bandgap perovskite solar cells achieved a power conversion efficiency of 13.8%, which is the record result for conventional device structures to date.

Chenyi Yang, Ningning Liang, Long Ye, Harald Ade, Xiaotao Yuan, Jianhui Hou

Organic Electronics 68 (2019) 15

https://doi.org/10.1016/j.orgel.2019.01.047

Toshinori Matsushima, Chuanjiang Qin, Kenichi Goushi, Fatima Bencheikh, Takeshi Komino, Matthew Leyden, Atula S. D. Sandanayaka, and Chihaya Adachi

Adv. Mater. 2018, 1802662

https://doi.org/10.1002/adma.201802662

Abstract:
The development of host materials with high performance is essential for fabrication of efficient and stable organic light-emitting diodes (OLEDs). Although host materials used in OLEDs are typically organics, in this study, it is shown that the organic–inorganic perovskite CH3NH3PbCl3 (MAPbCl3) can be used as a host layer for OLEDs. Vacuum-evaporated MAPbCl3 films have a wide band gap of about 3 eV and very high and relatively balanced hole and electron mobilities, which are suitable for the host material. Photoluminescence and electroluminescence take place through energy transfer from MAPbCl3 to an organic emitter in films. Incorporation of an MAPbCl3 host layer into OLEDs leads to a reduction of driving voltage and enhancement of external quantum efficiency as compared to devices with a conventional organic host layer. Additionally, OLEDs with an MAPbCl3 host layer demonstrate very good operational stability under continuous current operation. These results can be extensively applied to organic- and perovskite-based optoelectronics.

Matthias Diethelm, Quirin Grossmann, Andreas Schiller, Evelyne Knapp, Sandra Jenatsch, Maciej Kawecki, Frank Nüesch, and Roland Hany

Adv. Optical Mater. 2018, 1801278

https://doi.org/10.1002/adom.201801278

Abstract:
Effects of ion concentration and active layer thickness play a critical role on the performance of light-emitting electrochemical cells. Expanding on a pioneering materials system comprising the super yellow (SY) polymer and the electrolyte trimethylolpropane ethoxylate (TMPE)/Li+CF3SO3 -, it is reported that a slightly lowered salt concentration and layer thickness result in a substantial efficiency increase, and that this increase is confined to a narrow concentration and thickness range. For a film thickness of 70 nm, a blend ratio SY:TMPE:Li+CF3SO3 - = 1:0.075:0.0225, and a current of 7.7 mA cm-2 the current efficacy is 11.6 cd A-1, on a par with SY light-emitting diodes. The optimized salt content can be explained by increased exciton quenching at higher concentrations and hindered carrier injection and conduction at lower concentrations, while the optical dependence on the layer thickness is due to weak microcavity effects. A comprehensive optical modeling study is presented, which includes the doping-induced changes of the refractive indices and self-absorption losses due the emission–absorption overlap of intrinsic and doped SY. The analysis indicates either a thickness-independent emitter position (EP) close to the anode or a thickness-dependent EP, shifted to the cathode for increased thicknesses.

Ru-Ze Liang, Maxime Babics, Victoria Savikhin, Weimin Zhang, Vincent M. Le Corre, Sergei Lopatin, Zhipeng Kan, Yuliar Firdaus, Shengjian Liu, Iain McCulloch, Michael F. Toney, and Pierre M. Beaujuge

Adv. Energy Mater. 2018, 8, 1800264

https://doi.org/10.1002/aenm.201800264

Yi-Ting Lee, Po-Chen Tseng, Takeshi Komino, Masashi Mamada, Ruby Janet Ortiz, Man-Kit Leung, Tien-Lung Chiu, Chi-Feng Lin, Jiun-Haw Lee, Chihaya Adachi, Chao-Tsen Chen, and Chin-Ti Chen

ACS Appl. Mater. Interfaces, 2018

https://doi.org/10.1021/acsami.8b16199

Yingying Zhang, Xiong Li, Denghui Xu, Fanwen Meng, Rong Hu, Jia Zhao

Surface & Coatings Technology, 2018

https://doi.org/10.1016/j.surfcoat.2018.11.074

Akanksha Jetly, Rajesh Mehra

Optical Materials 88, 304 (2019)

https://doi.org/10.1016/j.optmat.2018.11.051

Francesco Pagani, Evelyn Stilp, Reto Pfenninger, Eduardo Cuervo Reyes, Arndt Remhof, Zoltan Balogh-Michels, Antonia Neels, Jordi Sastre-Pellicer, Michael Stiefel, Max Döbeli, Marta D Rossell, Rolf Erni, Jennifer L.M. Rupp, and Corsin Battaglia

ACS Appl. Mater. Interfaces, 2018

https://doi.org/10.1021/acsami.8b16519

Abstract:

Using an epitaxial thin-film model system deposited by pulsed laser deposition (PLD), we study the Li-ion conductivity in Li4Ti5O12, a common anode material for Li-ion batteries. Epitaxy, phase purity, and film composition across the film thickness are verified employing out-of-plane and in-plane X-ray diffraction, transmission electron microscopy, time-of-flight mass spectrometry, and elastic recoil detection analysis. We find that epitaxial Li4Ti5O12 behaves like an ideal ionic conductor that is well described by a parallel RC equivalent circuit, with an ionic conductivity of 2.5 × 10–5 S/cm at 230 °C and an activation energy of 0.79 eV in the measured temperature range of 205 to 350 °C. Differently, in a co-deposited polycrystalline Li4Ti5O12 thin film with an average in-plane grain size of <10 nm, a more complex behavior with contributions from two distinct processes is observed. Ultimately, epitaxial Li4Ti5O12 thin films can be grown by PLD and reveal suitable transport properties for further implementation as zero-strain and grain boundary free anodes in future solid-state microbattery designs.

Jwo-Huei Jou, Tzu-Chieh Tai, Yu-Ting Su, Hui-Huan Yu, Chi-Heng Chiang, Sudam D. Chavhan, You-Ting Lin, Jing-Jong Shyue, and Tzu-Wei Liang

Physica status solidi A, 2018

https://doi.org/10.1002/pssa.201800390

Indunil Angunawela, Long Ye, Haijun Bin, Zhi-Guo Zhang, Abay Gadisa, Yongfang Li and Harald Ade

Materials Chemistry Frontiers, 2018

https://doi.org/10.1039/C8QM00503F

Taesoo Kim, Yuliar Firdaus, Ahmad R. Kirmani, Ru-Ze Liang, Hanlin Hu, Mengxia Liu, Abdulrahman El Labban, Sjoerd Hoogland, Pierre M. Beaujuge, Edward H. Sargent, and Aram Amassian

ACS Energy Letters 3, 1307 (2018)

https://doi.org/10.1021/acsenergylett.8b00460

Yuan Xiong, Long Ye, Abay Gadisa, Qianqian Zhang, Jeromy James Rech, Wei You, and Harald Ade

Advanced Functional Materials 2018, 1806262

https://doi.org/10.1002/adfm.201806262

Michele De Bastiani, Erkan Aydin, Thomas Allen, Daniel Walter, Andreas Fell, Jun Peng, Nicola Gasparini, Joel Troughton, Derya Baran, Klaus Weber, Thomas P. White, and Stefaan De Wolf

Advanced Electronic Materials 2018, 1800500

https://doi.org/10.1002/aelm.201800500

Abstract:
Charge accumulation at the electron and hole transport layers generates anomalous electrical behavior in perovskite solar cells (PSCs). Hysteresis in the current–voltage characteristic and recombination at the interfaces are the clearest manifestations of this phenomenon, which compromises device performance and stability. Here, the underlying charge-carrier dynamics of a variety of PSCs are investigated by analyzing their transient photocurrent response. Towards shorter time scales, PSCs often show increasingly severe hysteretic responses. This phenomenon is correlated with the presence of interfacial accumulated charges that hinders the photogenerated carrier extraction process. However, introducing passivating contacts improves the carrier-injection properties and the devices become completely hysteresis free. These results underline the importance of contact passivation for PSCs and the need to further develop new passivating interlayers that simultaneously eliminate charge-carrier recombination and provide selective transport for each carrier type at the PSC’s contacts.

S. Altazin, C. Kirsch, E. Knapp, A. Stous, and B. Ruhstaller

Journal of Applied Physics 124, 135501 (2018)

https://doi.org/10.1063/1.5043245

Abstract:
We present a new approach to simulate the transport of charges across organic/organic layer interfaces in organic semiconductor devices. This approach combines the drift-diffusion formalism away from the interface with a hopping description of the charge transport in the vicinity of the interface. It has been implemented in the commercial software SETFOS allowing for fast simulations of the complete device. This new model takes into account both recombination and generation mechanisms across the interface enabling the modeling of charge-generation/recombination interfaces for the numerical simulation of tandem devices. Using this approach, it is also possible to simulate devices using 1,4,5,8,9,11-Hexaazatriphenylenehexacarbonitrile as a hole-injection layer. This particular material has a very deep HOMO level (approximately 9.5 eV), which would seemingly prevent such a layer to be used as a hole-injection material in the framework of traditional drift-diffusion models.

Kyungnam Kang, Kyoung-Youm Kim, and Jungho Kim

Optics Express 26, A955 (2018)

https://doi.org/10.1364/OE.26.00A955

Akanksha Jetly and RajeshMehra

International Journal of Optics

Volume 2018, Article ID 9458530

https://doi.org/10.1155/2018/9458530

Jin Xu, Andreas Sandström, Erik Mattias Lindh, Wei Yang, Shi Tang, and Ludvig Edman

ACS Appl. Mater. Interf., 2018. 10 , 33380

https://doi.org/10.1021/acsami.8b13036

Stéphane Altazin, Lieven Penninck, and Beat Ruhstaller

Handbook of Organic Light-Emitting Diodes, Springer Nature 2018

https://doi.org/10.1007/978-4-431-55761-6_21-1

S. Jenatsch, S. Altazin, P.-A. Will, M. T. Neukom, E. Knapp, S. Züfle, S. Lenk, S. Reineke, and B. Ruhstaller

Journal of Applied Physics 124, 105501 (2018)

https://doi.org/10.1063/1.5044494

Abstract:
Single-carrier devices are an excellent model system to study charge injection and charge transport properties of (doped) transport layers and to draw conclusions about organic electronics devices in which they are used. By combining steady-state and impedance measurements at varying temperatures of hole-only devices with different intrinsic layer thicknesses, we are able to determine all relevant material parameters, such as the charge mobility and the injection barrier. Furthermore, the correlation and sensitivity analyses reveal that the proposed approach to study these devices is especially well suited to extract the effective doping density, a parameter which cannot be easily determined otherwise. The effective doping density is crucial in organic light-emitting diodes (OLEDs) for realizing efficient injection, charge balance, and lateral conductivity in display or lighting applications. With the fitted drift-diffusion device model, we are further able to explain the extraordinary two-plateau capacitance–frequency curve of these hole-only devices, which originates from charges that flow into the intrinsic layer at zero applied offset voltage. We demonstrate that the observation of this behaviour is a direct indication for ideal charge injection properties and the observed capacitance–frequency feature is linked to the charge carrier mobility in the intrinsic layer. The extracted material parameters may directly be used to simulate and optimize full OLED devices employing the investigated hole-injection and -transport materials.

Markus Regnat, Kurt P. Pernstich, Simon Züfle, and Beat Ruhstaller

ACS Applied Materials & Interfaces 10,31552 (2018)

https://doi.org/10.1021/acsami.8b09595

Abstract:
From s-polarized, angle-dependent measurements of the electroluminescence spectra in a three-layer phosphorescent organic light-emitting diode, we calculate the exciton distribution inside the 35 nm thick emission layer. The shape of the exciton profile changes with the applied bias due to differing field dependencies of the electron and hole mobilities. A split emission zone with high exciton densities at both sides of the emission layer is obtained, which is explained by the presence of energy barriers and similar electron and hole mobilities. A peak in the transient electroluminescence signal after turn-off and the application of a reverse bias is identified as a signature of a split emission zone.

Dario Di Carlo Rasi, Koen H. Hendriks, Martijn M. Wienk, and René A. J. Janssen

Advanced Materials, 2018, 1803836

https://doi.org/10.1002/adma.201803836

Abstract:

A monolithic two-terminal solution-processed quadruple junction polymer solar cell in an n–i–p (inverted) configuration with four complementary polymer:fullerene active bulk-heterojunction layers is presented. The subcells possess different optical bandgaps ranging from 1.90 to 1.13 eV. Optical modeling using the transfer matrix formalism enables prediction of the fraction of absorbed photons from sunlight in each subcell and determine the optimal combination of layer thicknesses. The quadruple junction cell features an open-circuit voltage of 2.45 V and has a power conversion efficiency of 7.6%, only slightly less than the modeled value of 8.2%. The external quantum efficiency spectrum, determined with appropriate light and voltage bias conditions, exhibits in general an excellent agreement with modeled spectrum. The device performance is presently limited by bimolecular recombination, which prevents using thick photoactive layers that could absorb light more efficiently.

Hyunkoo Lee, Jonghee Lee, Jeong-Ik Lee and Nam Sung Cho

Electronics 7,155 (2018)

https://doi.org/10.3390/electronics7090155

Hyunsu Cho, Chul Woong Joo, Byoung-Hwa Kwon, Nam Sung Cho, Jonghee Lee

Organic Electronics 62, 72 (2018)

https://doi.org/10.1016/j.orgel.2018.07.016

S. Züfle, S. Altazin, A. Hofmann, L. Jäger, M. T. Neukom, W. Brütting, and B. Ruhstaller

J. Appl. Phys. 122, 115502, 2017.

https://dx.doi.org/10.1063/1.4992041

Abstract:
Charge carrier transport in organic semiconductor devices is thermally activated with characteristic activation energies in the range of 0.2–0.6 eV, leading to strongly temperature-dependent behaviour. For designing efficient organic semiconductor materials and devices, it is therefore indispensable to understand the origin of these activation energies. We propose that in bilayer organic light-emitting diodes (OLEDs) employing a polar electron transport layer, as well as in metal-insulator-semiconductor (MIS) devices, the hole injection barrier Einj and the hole mobility activation energy El can be decoupled from each other if temperature-dependent capacitancefrequency (C-f-T) and MIS-CELIV (charge extraction by linearly increasing voltage) experiments are combined. While the C-f-T signal contains information of both injection and transport, the CELIV current is expected to be insensitive to the electrode injection properties. We employ numerical drift-diffusion simulations to investigate the accuracy of this analytical parameter extraction approach and to develop criteria for its validity. We show that the implicit assumption of constant charge density and field profiles leads to systematic errors in determining the activation energies. Thus, one should be aware of the intrinsic limitations of the analytical Arrhenius fit, and for more accurate parameter determination a full drift-diffusion modelling is advised. Applying the analytical method to a standard bilayer OLED, we find that the total activation energy of 0.5 eV for the hole current can be split into contributions of 0.25 eV each for injection barrier and mobility. Finally, we also discuss the broader applicability of this method for other device stacks and material combinations.

Jwo-Huei Jou, Jia-Wei Weng, Sudam Dhudaku Chavhan, Rohit Ashok Kumar Yadav, Tzu-Wei Liang

Journal of Physics D 51 (45), 454002 (2018)

https://doi.org/10.1088/1361-6463/aad951

Jung Hyuk Im, Kyung-Tae Kang, Jong Sun Choi and Kwan Hyun Cho

Journal of Luminescence 203, 540 (2018)

https://doi.org/10.1016/j.jlumin.2018.07.011

Bei Yang, Yu Chen, Yong Cui, Delong Liu, Bowei Xu and Jianhui Hou

Adv. Energy Mater. 2018, 8, 1800698

https://doi.org/10.1002/aenm.201800698

Rohit Ashok Kumar Yadav, Deepak Kumar Dubey, Sun-Zen Chen, Sujith Sudheendran Swayamprabha, Tzu-Wei Liang, Jwo-Huei Jou

MRS Advances, 2018, 3, 3445

https://doi.org/10.1557/adv.2018.365

Sheng Bi, Zhongliang Ouyang, Shoieb Shaik and Dawen Li

Scientific Reports 8, 9574 (2018)

https://doi.org/10.1038/s41598-018-27868-2

Shuai-Shuai Meng, Yan-Qing Li and Jian-Xin Tang

Organic Electronics 61, 351 (2018)

https://doi.org/10.1016/j.orgel.2018.06.014

Laura Ciammaruchi et al.

Journal of Materials Research 33 (13), pp. 1909-1924 (2018)

https://doi.org/10.1557/jmr.2018.163

Elisabeth Bodenstein, Matthias Schober, Marie Hoffmann, Christoph Metzner, Uwe Vogel

Journal of the SID, 2018 , 26, 555

DOI:10.1002/jsid.674

Alejandro N. Filippin, Tzu-Ying Lin, Michael Rawlence, Tanja Zünd, Kostiantyn Kravchyk, Jordi Sastre-Pellicer, Stefan G. Haass, Aneliia Wäckerlin, Maksym V. Kovalenkoab and Stephan Buecheler

RSC Adv., 2018, 8, 20304

DOI: 10.1039/C8RA02461H

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Abstract:

To obtain full advantage of state-of-the-art solid-state lithium-based batteries, produced by sequential deposition of high voltage cathodes and promising oxide-based electrolytes, the current collector must withstand high temperatures (>600 °C) in oxygen atmosphere. This imposes severe restrictions on the choice of materials for the first layer, usually the cathode current collector. It not only must be electrochemically stable at high voltage, but also remain conductive upon deposition and annealing of the subsequent layers without presenting a strong diffusion of its constituent elements into the cathode. A novel cathode current collector based on a Ni–Al–Cr superalloy with target composition Ni0.72Al0.18Cr0.10 is presented here. The suitability of this superalloy as a high voltage current collector was verified by determining its electrochemical stability at high voltage by crystallizing and cycling of LiCoO2 directly onto it.

Martin Neukom, Simon Züfle, Sandra Jenatsch, Beat Ruhstaller

Science Tech. Adv. Mater., 2018, 19, 291

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DOI: 10.1080/14686996.2018.1442091

Abstract:
We present an overview of opto-electronic characterization techniques for solar cells including light-induced charge extraction by linearly increasing voltage, impedance spectroscopy, transient photovoltage, charge extraction and more. Guidelines for the interpretation of experimental results are derived based on charge drift-diffusion simulations of solar cells with common performance limitations. It is investigated how nonidealities like charge injection barriers, traps and low mobilities among others manifest themselves in each of the studied cell characterization techniques. Moreover, comprehensive parameter extraction for an organic bulk-heterojunction solar cell comprising PCDTBT:PC70BM is demonstrated. The simulations reproduce measured results of 9 different experimental techniques. Parameter correlation is minimized due to the combination of various techniques. Thereby a route to comprehensive and accurate parameter extraction is identified.

Andrius Devižis, Sandra Jenatsch, Matthias Diethelm, Vidmantas Gulbinas, Frank Nüesch, Roland Hany

ACS Photonics, 2018, 5 (8), pp 3124-3131

DOI: 10.1021/acsphotonics.8b00358

Tzu-Hung Yeh, Chih-Chien Lee, Chun-Jen Shih, Gautham Kumar, Sajal Biring, Shun-Wei Liu

Organic Electronics 59, 266 (2018)

https://doi.org/10.1016/j.orgel.2018.05.014

S. Altazin, L. Stepanova, J. Werner, B. Niesen, C. Ballif, and B. Ruhstaller

Optics Express 26, A579 (2018)

https://doi.org/10.1364/OE.26.00A579

Abstract:
We present an optical model implemented in the commercial software SETFOS 4.6 for simulating perovskite/silicon monolithic tandem solar cells that exploit light scattering structures. In a first step we validate the model with experimental data of tandem solar cells that either use front- or rear-side textures and extract the internal quantum efficiency of the methyl-ammonium lead iodide (MALI) perovskite sub-cell. In a next step, the software is used to investigate the potential of different device architectures featuring a monolithic integration between the perovskite and silicon sub-cells and exploiting rear- as well as front-side textures for improved light harvesting. We find that, considering the available contact materials, the p-i-n solar cell architecture is the most promising with respect to achievable photocurrent for both flat and textured wafers. Finally, cesium-formamidinium-based perovskite materials with several bandgaps were synthetized, optically characterized and their potential in a tandem device was quantified by simulations. For the simulated layer stack and among the tested materials with bandgaps of 1.7 and 1.6 eV, the one with 1.6 eV bandgap was found to be the most promising, with a potential of reaching a power conversion efficiency of 31%. In order to achieve higher efficiencies using higher band-gap materials, parasitic absorptance in the blue spectral range should be further reduced.

Dario Di Carlo Rasi, Koen H. Hendriks, Gaël H. L. Heintges, Giulio Simone, Gerwin H. Gelinck, Veronique S. Gevaerts, Ronn Andriessen, Geert Pirotte,Wouter Maes, Weiwei Li, Martijn M. Wienk, and René A. J. Janssen

Sol. RRL, 2018, 2, 1800018

DOI: 10.1002/solr.201800018

Simon Züfle, Stéphane Altazin, Alexander Hofmann, Lars Jäger, Martin T. Neukom, Tobias D. Schmidt, Wolfgang Brütting, Beat Ruhstaller,

J. Appl. Phys. 121, 175501, 2017.

http://dx.doi.org/10.1063/1.4982903

Abstract:
We demonstrate the application of the CELIV (charge carrier extraction by linearly increasing voltage) technique to bilayer organic light-emitting devices (OLEDs) in order to selectively determine the hole mobility in N,N0-bis(1-naphthyl)-N,N0-diphenyl-1,10-biphenyl-4,40-diamine (a-NPD). In the CELIV technique, mobile charges in the active layer are extracted by applying a negative voltage ramp, leading to a peak superimposed to the measured displacement current whose temporal position is related to the charge carrier mobility. In fully operating devices, however, bipolar carrier transport and recombination complicate the analysis of CELIV transients as well as the assignment of the extracted mobility value to one charge carrier species. This has motivated a new approach of fabricating dedicated metal-insulator-semiconductor (MIS) devices, where the extraction current contains signatures of only one charge carrier type. In this work, we show that the MIS-CELIV concept can be employed in bilayer polar OLEDs as well, which are easy to fabricate using most common electron transport layers (ETLs), like Tris-(8-hydroxyquinoline)aluminum (Alq3). Due to the macroscopic polarization of the ETL, holes are already injected into the hole transport layer below the built-in voltage and accumulate at the internal interface with the ETL. This way, by a standard CELIV experiment only holes will be extracted, allowing us to determine their mobility. The approach can be established as a powerful way of selectively measuring charge mobilities in new materials in a standard device configuration.

Karen Strassel, Adrian Kaiser, Sandra Jenatsch, Anna C. Véron, Surendra B. Anantharaman, Erwin Hack, Matthias Diethelm, Frank Nüesch, Rian Aderne, Cristiano Legnani, Sergii Yakunin, Marco Cremona, and Roland Hany

ACS Appl. Mater. Interf., 2018, 10, 11063

DOI: 10.1021/acsami.8b00047

Amin Salehi, Ying Chen, Xiangyu Fu, Cheng Peng, and Franky So

ACS Appl. Mater. Interf., 2018, 10, 9595

https://pubs.acs.org/doi/10.1021/acsami.7b18514

So-Ra Park and Min Chul Suh

Optics Express, 2018, 26, 4979

https://doi.org/10.1364/OE.26.004979

Lin-Song Cui, Shi-Bin Ruan, Fatima Bencheikh, Ryo Nagata, Lei Zhang, Ko Inada, Hajime Nakanotani, Liang-Sheng Liao & Chihaya Adachi

Nature Communications, 2017, 8, 2250

DOI: 10.1038/s41467-017-02419-x

Monica Morales-Masis, Stefaan De Wolf, Rachel Woods-Robinson, Joel W. Ager, and Christophe Ballif

Adv. Electron. Mater. 2017, 1600529

https://dx.doi.org/10.1002/aelm.201600529

Lei Wang, Sandra Jenatsch, Beat Ruhstaller, Christian Hinderling, Donatas Gesevicius, Roland Hany, and Frank Nüesch

Advanced Functional Materials 28,1705724 (2018)

DOI: 10.1002/adfm.201705724

Matthias Diethelm, Lieven Penninck, Stéphane Altazin, Roman Hiestand, Christoph Kirsch & Beat Ruhstaller

Journal of Information Display, 2018, 19, 61

DOI: 10.1080/15980316.2018.1428232

Abstract:
The resolution of organic light-emitting diode (OLED) displays is increasing steadily as these displays are adopted for mobile and virtual reality (VR) devices. This leads to a stronger pixel crosstalk effect, where the neighbors of active pixels unintentionally emit light due to a lateral electric current between the pixels. Recently, the crosstalk was quantified by measuring the current flowing through the common hole transport layer between the neighboring pixels and comparing it to the current through the active pixel diode [S.-K. Kwon, K.-S. Kim, H.-C. Choi and J. H. Kwon, presented at the International Meeting on Information Display, Jeju, South Korea, 2016]. The measurements showed that the crosstalk is more crucial for low light levels. In such cases, the intended and parasitic currents are similar. The simulations performed in this study validated these measurement results. By simulations, we quantify the crosstalk current through the diode. The luminous intensity can be calculated with the measured current efficiency of the diodes. For low light levels, the unintended luminance can reach up to 40% of the intended luminance. The luminance due to pixel crosstalk is perceivable by humans. This effect should be considered for OLED displays with resolutions higher than 300 PPI.

Martin Thomas Neukom, Simon Züfle, Evelyne Knapp, Mohammed Makha, Roland Hany, Beat Ruhstaller

Solar Energy Materials and Solar Cells 169 (2017) 159–166

http://dx.doi.org/10.1016/j.solmat.2017.05.021

Abstract:
There is increasing evidence that the presence of mobile ions in perovskite solar cells can cause a current-voltage curve hysteresis. However, it is still subject of ongoing debates how exactly mobile ions influence the device operation. We use drift-diffusion simulations incorporating mobile ions to describe IV-curves of preconditioned methylammonium lead iodide perovskite solar cells and compare them with experimental results. Our simulation results show that the hysteresis depends on the extent of surface recombination and on the diffusion length of charge carriers. We provide a detailed explanation for the reduced hysteresis of perovskite solar cells with high power conversion efficiencies. We find that in high-efficiency solar cells ion migration is still present, but does not cause a hysteresis effect. In these devices charge extraction is mainly driven by diffusion of free electrons and holes.

Dae-Hyeon Kim, Anthony D’Aléo, Xian-Kai Chen, Atula D. S. Sandanayaka, Dandan Yao, Li Zhao, Takeshi Komino, Elena Zaborova, Gabriel Canard, Youichi Tsuchiya, Eunyoung Choi, Jeong Weon Wu, Frédéric Fages, Jean-Luc Brédas, Jean-Charles Ribierre and Chihaya Adachi

Nature Photonics, Vol. 12, February 2018. p. 98–104

https://doi.org/10.1038/s41566-017-0087-y

Sandra Jenatsch, Markus Regnat, Roland Hany, Matthias Diethelm, Frank Alain Nüesch, and Beat Ruhstaller

ACS Photonics 5, 1591 (2018)

DOI: 10.1021/acsphotonics.8b00047

Abstract:
Light-emitting electrochemical cells (LECs) are one of the simplest electroluminescent devices and consist of a single emissive organic/salt layer sandwiched between two electrodes. The unique attribute of an operated LEC is the development of a pdoped/ intrinsic/n-doped (p-i-n) structure in the active layer in which the doped regions allow for facile transport of electronic charges to the intrinsic region, where charge recombination and light emission occur. However, due to the complex and simultaneous motion of ionic and electronic charges, the examination of the p-i- n structure and the zone where the light is emitted (EZ) is challenging during operation. By analyzing incident photon-tocurrent conversion efficiency and angular emission measurements with optical simulations, and correlating the results with capacitance measurements, we are able to obtain a clear picture of the p-i-n situation and the EZ within the active layer of a sandwich-type LEC during operation. It is found that the p-doped zone grows to the center of the active layer while the EZ stays closer to the metal electrode and is unchanged over time. Furthermore, optical simulations reveal that the determined EZ limits the external quantum efficiency of the LEC by outcoupling efficiencies of less than 10%.

Ru-Ze Liang, Maxime Babics, Akmaral Seitkhan, Kai Wang, Paul Bythell Geraghty, Sergei Lopatin, Federico Cruciani, Yuliar Firdaus, Marco Caporuscio, David J. Jones and Pierre M. Beaujuge

Advanced Functional Materials 28, 1705464 (2019)

DOI: 10.1002/adfm.201705464

Donatas Gesevicius, Antonia Neels, Sandra Jenatsch, Erwin Hack, Lucas Viani, Stavros Athanasopoulos, Frank Nüesch, and Jakob Heier

Advanced Science 5,1700496 (2018)

DOI: 10.1002/advs.201700496

S. Altazin, L. Stepanova, K. Lapagna, P. Losio, J. Werner, B. Niesen, A. Dabirian, M. Morales-Masis, S. de Wolf, C. Ballif, B. Ruhstaller

32nd European Photovoltaic Solar Energy Conference and Exhibition, pp 1276 - 1279 , 2016

https://doi.org/10.4229/EUPVSEC20162016-3DV.2.2

Hai-Ching Su

ChemPlusChem 83, 197 (2018)

DOI: 10.1002/cplu.201700455

Xin Song, Nicola Gasparini, and Derya Baran

Advanced Electronic Materials 4,1700358 (2018)

DOI: 10.1002/aelm.201700358

Mohammed F. Al-Mudhaffera, Matthew J. Griffith, Krishna Feron, Nicolas C. Nicolaidis, Nathan A. Cooling, Xiaojing Zhou, John Holdsworth, Warwick J. Belcher, Paul C. Dastoor

Solar Energy Materials and Solar Cells 175, 77 (2018)

http://dx.doi.org/10.1016/j.solmat.2017.09.007

Nobuhiro Nakamura, Junghwan Kim, Koji Yamamoto, Satoru Watanabe, and Hideo Hosono

Organic Electronics 51, 103 (2017)

10.1016/j.orgel.2017.09.016

Yea-Fen Jang, Tzu-Chun Lin, Jhih-Yan Guo, Chien-Ming Fan Chiang, Ming-Lun Wu, Hsin-Yi Shen, Tsung-Cheng Chen, Zu-Po Yang, Ya-Ju Lee, Hai-Ching Su, Chih-Hao Chang, Shun-Wei Liu

Organic Electronics, 2017, 51, 129

https://doi.org/10.1016/j.orgel.2017.09.024

Jung-Yu Li, Shih-Pu Chen, Huei-Jhen Siao, Jin-Han Wu, Guan-Yu Chen, Cheng-Chang Chen, Shu-Yi Ho, Yi-
Ping Lin, Hong-Hui Hsu, Jin-Sheng Lin, Ming-Shan Jeng, Nai-Chuan Chen, Hui-Kai Zeng, and Jenh-Yih Juang

Appl. Phys. Lett. 111, 093301 (2017)

doi: 10.1063/1.5000499

Long Ye, Yuan Xiong, Sunsun Li, Masoud Ghasemi, Nrup Balar, Johnathan Turner, Abay Gadisa, Jianhui Hou, Brendan T. O’Connor, and Harald Ade

Advanced Functional Materials 27,1702016 (2017)

DOI: 10.1002/adfm.201702016

Takeshi Gotanda, Shigehiko Mori, Haruhi Oooka, Hyangmi Jung, Hideyuki Nakao, Kenji Todori, and Yutaka Nakai

Journal of Materials Research 32,2700 (2017)

DOI: 10.1557/jmr.2017.264

Abstract:
Perovskite solar cells are promising for realizing high power conversion efficiency (PCE) with low manufacturing costs, but efficient coating methods are needed for commercialization. Here, a gas blowing method was used to fabricate perovskite solar cells and was found to create a smooth perovskite layer and to prevent voids in large-area cells, when organic materials were used as scaffolds for forming the perovskite. A PCE of 13% in a 1 cm2 active area is achieved by tuning the band-gap energy of MAPbX3 via substitution of Br for I ions in X sites. Incorporation of a poly(3,4-ethylenedioxythiophene) hole transport layer with a higher work function increased the open circuit voltage of the solar cells. All layers of the cells were fabricated at low temperatures (,140 °C), which makes it possible to incorporate a polymer substrate for producing flexible solar cells and high-throughput fabrication.

T. Lanz, K. Lapagna, S. Altazin, M. Boccard, F.J. Haug, C. Ballif, B. Ruhstaller

Optics Express 23 (11), A539-A546, (2015)

https://doi.org/10.1364/OE.23.00A539

C Kirsch, S Altazin, R Hiestand, T Beierlein, R Ferrini, T Offermans, L Penninck, B Ruhstaller

Int. Jnl. of Multiphysics Volume 11 · Number 2 · 2017

S. Olivier, E. Ishow, S. Meunier Della-Gatta, T. Maindron

Organic Electronics 49, 24 (2017)

DOI: 10.1016/j.orgel.2017.06.017

S. Jenatsch, L. Wang, N. Leclaire, E. Hack, R. Steim, S.B. Anantharaman, J. Heier, B. Ruhstaller, L. Penninck, F. Nüesch, R. Hany

Organic Electronics 48, 77 (2017),

doi: 10.1016/j.orgel.2017.05.038.

Marco Natali, Santiago D. Quiroga, Luca Passoni, Luigino Criante, Emilia Benvenuti, Gabriele Bolognini, Laura Favaretto, Manuela Melucci, Michele Muccini, Francesco Scotognella, Fabio Di Fonzo, and Stefano Toffanin

Adv. Funct. Mater. 2017, 1605164

DOI: 10.1002/adfm.201605164

Amin Salehi, Szuheng Ho, Ying Chen, Cheng Peng, Hartmut Yersin, and Franky So

Adv. Optical Mater. 2017, 1700197

DOI: 10.1002/adom.201700197

T. Lanz, E. M. Lindha and L. Edmana

Journal of Materials Chemistry C 5, 4706 (2017)

DOI: 10.1039/C7TC01022B

Chul Woong Joo, Keunsoo Lee, Jonghee Lee, Hyunsu Cho, Jin-Wook Shin, Nam Sung Cho, Jaehyun Moon

Journal of Luminescence 187 (2017) 433–440

http://dx.doi.org/10.1016/j.jlumin.2017.03.057

L. Zhao, T. Komino, D. Hyeon Kim, M. Hasnan Sazzad, D. Pitrat, J.-C. Mulatier, C. Andraud, J.-C. Ribierre and C. Adachi
J. Mater. Chem. C, 2016, 4, 11557

DOI: 10.1039/c6tc02861f

Serkan Esiner, Gijs W. P. van Pruissen, Martijn M. Wienk and René A. J. Janssen

J. Mater. Chem. A, 2016,4, 5107-5114

DOI: 10.1039/C5TA10459A

Jan A. Mayer, Benjamin Gallinet, Ton Offermans, Igor Zhurminsky, Rolando Ferrini

Solar Energy Materials & Solar Cells 163 (2017) 51–57
DOI: http://dx.doi.org/10.1016/j.solmat.2017.01.015

D. H. Kim, K. Inada, L. Zhao, T. Komino, N. Matsumoto, J. C. Ribierre, and C. Adachi

J. Mater. Chem. C 5,1216 (2017)

DOI: 10.1039/C6TC04786F

Martin Neukom,

Msc Thesis, Jan 2016.
arXiv:1611.06425 [cond-mat.mtrl-sci]
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Abstract:
Transient opto-electrical measurements of methylammonium lead iodide (MALI) perovskite solar cells (PSCs) are performed and analyzed in order to elucidate the operating mechanisms. The current response to a light pulse or voltage pulse shows an extraordinarily broad dynamic range covering 9 orders of magnitude in time – from microseconds to minutes – until steady-state is reached. Evidence of a slowly changing charge density at the perovskite layer boundaries is found, which is most probably caused by mobile ions. Currentvoltage curves (IV curves) are measured with very fast scan-rate after keeping the cell for several seconds at a constant voltage as proposed by Tress et al. Numerical drift-diffusion simulations reproduce the measured IV curves using different distributions of ions in the model. Analysing the band diagram of the simulation result sheds light on the operating mechanism. To further investigate the effects at short time scales (below milliseconds) photo-generated charge extraction by linearly increasing voltage (photo-CELIV) experiments are performed. We postulate that mobility imbalance in combination with deep hole trapping leads to dynamic doping causing effects from microseconds to milliseconds. Comprehensive transient drift-diffusion simulations of the photo-CELIV experiments strengthen this hypothesis. This advanced characterization approach combining dynamic response measurements and numerical simulations represents a key step on the way to a comprehensive understanding of device working mechanisms in emerging perovskite solar cells.

Hyunsu Cho, Chul Woong Joo, Jonghee Lee, Hyunkoo Lee,
Jaehyun Moon, Jeong-IK Lee, Jun Yeob Lee, Youngjin Kang and
Nam Sung Cho

Optics Express 24, 24161 (2016)

http://dx.doi.org/10.1364/OE.24.024161

S. Altazin, S. Züfle, E. Knapp, C. Kirsch, T.D. Schmidt, L. Jäger, Y. Noguchi, W. Brütting, B. Ruhstaller

Organic Electronics 39 (2016) 244-249

http://dx.doi.org/10.1016/j.orgel.2016.10.014

T. R. Andersen, F. Almyahi, N. A. Cooling, D. Elkington, L. Wiggins, A. Fahya, K. Feron, B. Vaughan, M. J. Griffith, A. J. Mozer, C. Saekung, G. G. Wallace, W. J. Belcher, and P. C. Dastoor.

Journal of Materials Chemistry A 4, 15986 (2016)

DOI: 10.1039/x0xx00000x

H. Jin , C. Tao , M. Velusamy , M. Aljada , Y. Zhang , M. Hambsch ,
P. L. Burn,  and P. Meredith

Advanced Mataterials24, p. 2572-2577 (2012)
DOI: 10.1002/adma.201104896

Alessia Senes, Stefan C. J. Meskers, Wijnand M. Dijkstra, Jacobus J. van Franeker, Stéphane Altazin, Joanne S. Wilson and René A. J. Janssen

J. Mater. Chem. C, 2016, 4, 6302

https://doi.org/10.1039/c5tc03481g

T. Komino, Y. Sagara, H. Tanaka, Y. Oki, N. Nakamura, H.Fujimoto, and C. Adachi

Applied Physics Letters 108, 241106 (2016)

doi: 10.1063/1.4954163

N. A. Cooling, E. F. Barnes, F. Almyahi, K. Feron, M. Al-Mudhaffer, A. Al-Ahmad, B. Vaughan , T. R. Andersen , M. J. Griffith , A. S. Hart , A. G. Lyons , W. J. Belcher , P. C. Dastoor

J. Mater. Chem. A 4, 10274 (2016)

DOI: 10.1039/C6TA04191D

S. Altazin, S. Züfle, E. Knapp, C. Kirsch, T.D. Schmidt, L. Jäger, W. Brütting, B. Ruhstaller

SID Digest of Technical Papers 47, 1750 (2016)

https://doi.org/10.1002/sdtp.11059

Stéphane Altazin, Clément Reynaud, Ursula M. Mayer, Thomas Lanz, Kevin Lapagna, Reto Knaack, Lieven Penninck, Christoph Kirsch, Kurt P. Pernstich, Stephan Harkema, Dorothee Hermes, Beat Ruhstaller

SID Digest of Technical Papers 46, 564 (2015)

https://doi.org/10.1002/sdtp.10478

M. L. Inche Ibrahim

Journal Of Applied Physics 119, 154504 (2016)

DOI: http://dx.doi.org/10.1063/1.4946038

Raju Lampande, Gyeong Woo Kim, Mi Jin Park, Byeong Yeob Kang, Jang Hyuk Kwonn

Solar Energy Materials & Solar Cells 151 (2016) 162–168

http://dx.doi.org/10.1016/j.solmat.2016.03.005
 

Hironori Kaji, Hajime Suzuki, Tatsuya Fukushima, Katsuyuki Shizu, Katsuaki Suzuki, Shosei Kubo, Takeshi Komino, Hajime Oiwa, Furitsu Suzuki, Atsushi Wakamiya, Yasujiro Murata and Chihaya Adachi

Nature Communications 6, 8476 (2015)

https://doi.org/10.1038/ncomms9476

S. Züfle, M. T. Neukom, S. Altazin, M. Zinggeler, M. Chrapa, T. Offermans, B. Ruhstaller,

Adv. Energy Mater., 1500835, 2015.

https://doi.org/10.1002/aenm.201500835

Abstract:

In standard unencapsulated poly(3‐hexylthiophene):[6,6]‐phenyl C61‐butyric acid methyl ester solar cells exposed to humid air, the oxidation of the aluminum cathode is known to be a key degradation mechanism. Water that enters the device at the edges and through pinholes diffuses to the organic–electrode interface. The forming oxide acts as a thin insulating layer that gives rise to an injection/extraction barrier and leads to a loss in the device current. In order to understand this behavior in detail various steady‐state, transient, and impedance measurement techniques are performed in combination with drift‐diffusion simulations. With this combinatorial approach, the dominant degradation mechanism is confirmed to be the development of a blocking interface layer. This layer grows laterally leading to a loss in effective area due to the rapid local oxidation of the aluminum layer. Thus by combining multiple electrical techniques and optoelectrical simulations the dominant degradation mechanism can be evaluated. The same methodology is also beneficial for more stable and efficient novel solar cells.

Stéphane Altazin, Kevin Lapagna, Thomas Lanz, Christoph Kirsch, Reto Knaack, Beat Ruhstaller

SID Digest of Technical Papers 45, 576 (2014)

https://doi.org/10.1002/j.2168-0159.2014.tb00151.x

Stéphane Altazin, Benjamin Perucco, Nicolò Pagan, Kevin Lapagna, Thomas Lanz, Reto Knaack, Evelyne Knapp, Beat Ruhstaller

SID Digest of Technical Papers 44, 1486 (2013)

https://doi.org/10.1002/j.2168-0159.2013.tb06529.x

S. Jenatsch, R. Hany, A.C. Véron, M. Neukom, S. Züfle, A. Borgschulte, B. Ruhstaller, F. Nüesch

J. Phys. Chem. C, 118 (30), 17036, 2014

https://pubs.acs.org/doi/10.1021/jp5005314

M. Eck, C.V. Phama, S. Züfle, M. Neukom, M. Seßler, D. Scheunemann, E. Erdem, S. Weber, H. Borchert, B. Ruhstaller, M. Krüger

Physical Chemistry Chemical Physics, 16 (24) 12251, 2014

https://dx.doi.org/10.1039/c4cp01566e

M.T. Neukom, S. Züfle, B. Ruhstaller

Organic Electronics 13, 2910 (2012)

http://dx.doi.org/10.1016/j.orgel.2012.09.008

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J. Singh, M. Narayan

Nanoscience and Technology, 1(1), 8, 2013.

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S. Zhang, Z. Liu, X. Wang, S. Yue, Z. Zhang, Q. Wu, G. Xie, Q. Xue, Y. Chen, P. Wang, R. Gu, D. Qu, Y. Zhao, S. Liu

Thin Solid Films 537, 221 (2013)

http://dx.doi.org/10.1016/j.tsf.2013.04.036

G. Liaptsis, K. Meerholz

Adv. Funct. Mater., 23, 359-365, 2013

https://doi.org/10.1002/adfm.201201197

S. Zhang, G. Xie, Q. Xue, Z. Zhang, L. Zhao, Y. Luo, S. Yue, Y. Zhao, S. Liu

Thin Solid Films 520, 2966 (2012)

https://doi.org/10.1016/j.tsf.2011.10.148

E. Knapp, B. Ruhstaller

Journal of Applied Physics 112,024519 (2012)

http://dx.doi.org/10.1063/1.4739303

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B. Perucco, N.A. Reinke, D. Rezzonico, E. Knapp, S. Harkema, B. Ruhstaller

Organic Electronics 13, 1827 (2012)

http://dx.doi.org/10.1016/j.orgel.2012.05.053

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J. Hauss, T. Bocksrocker, B. Riedel, U. Lemmer, M. Gerken,

Optics Express 19, a851 (2011)

https://doi.org/10.1364/OE.19.00A851

U. Hörmann, J. Wagner, M. Gruber, A. Opitz, W. Brütting

Physica Status Solidi Rapid Research Letters, 5, 241 (2011)

https://doi.org/10.1002/pssr.201105238

V.S. Gevaerts, J.A. Koster, M.M. Wienk, R.A. Janssen

ACS Applied Materials & Interfaces 3, 9, 3252 (2011)

https://pubs.acs.org/doi/10.1021/am200755m

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E. Knapp, B. Ruhstaller

Appl. Phys. Lett. 99, 9, 093304 (2011)

http://dx.doi.org/10.1063/1.3633109

M. Neukom, N.A. Reinke, B. Ruhstaller

Solar Energy 85, 1250 (2011)

https://doi.org/10.1016/j.solener.2011.02.028

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B. Ruhstaller, E. Knapp, B. Perucco, N. Reinke, D. Rezzonico and F. Müller

Optoelectronic Devices and Properties, Oleg Sergiyenko (Ed.)

ISBN 978-953-307-204-3, 2011

https://dx.doi.org/10.5772/14626

E. Knapp, B. Ruhstaller

Optical and Quantum Electronics, 42,667 (2011)

https://dx.doi.org/10.1007/s11082-011-9443-1

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D. Rezzonico, B. Perucco, E. Knapp, R. Häusermann, N.A. Reinke, F. Müller, B. Ruhstaller

Journal of Photonics for Energy, 1, 011005-1-11, 2011.

https://doi.org/10.1117/1.3528045

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F. Ventsch, M.C. Gather, K. Meerholz

Organic Electronics 11, 57 (2010)

https://dx.doi.org/10.1016/j.orgel.2009.09.026

S. Hamwi, J. Meyer, M. Kröger, T. Winkler, M. Witte, T. Riedl, A. Kahn, W. Kowalsky

Advanced Functional Materials 20,1762 (2010)

https://dx.doi.org/10.1002/adfm.201000301

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M. Mazzeo, F. Della Sala, F. Mariano, G. Melcarne, Y. Duan, S. D'Agostino , R. Cingolani, G. Gigli

Advanced Materials, 22, 4696-4700, 2010

https://doi.org/10.1002/adma.201001631

R. Mauer, I.A. Howard, F. Laquai

Journal of Physical Chemistry Letters, 1, 3500-3505, 2010

https://dx.doi.org/10.1021/jz101458y

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G. Xie, Z. Zhang, Q. Xue, S. Zhang, L. Zhao, Y. Luo, P. Chen, B. Quan, Y. Zhao, S. Liu

Organic Electronics 11, 2055, 2010

https://dx.doi.org/10.1016/j.orgel.2010.10.001

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E. Knapp, R. Häusermann, H.U. Schwarzenbach, B. Ruhstaller

Journal of Applied Physics, 108, 054504-0545012, 2010

http://dx.doi.org/10.1063/1.3475505

B. Perucco, N.A. Reinke, D. Rezzonico, M. Moos, and B. Ruhstaller

Optics Express, 18 (S2), A246-A260, 2010

https://doi.org/10.1364/OE.18.00A246

B. Perucco, N.A. Reinke, F. Müller, D. Rezzonico, and B. Ruhstaller

Proc. SPIE 7722, Organic Photonics IV, 77220F (2010)

doi: https://dx.doi.org/10.1117/12.853989

Mark L. Hildner, Jonathan M. Ziebarth

SID Digest of Technical Papers 42,1764 (2011)

https://doi.org/10.1889/1.3621234

G. Cheng, M. Mazzeo, S. D’Agostino, F. Della Sala, S. Carallo, G. Gigli

Optics Letters, 35 (5), 616-618, 2010

https://doi.org/10.1364/OL.35.000616

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P.M. Boland, T. Abdel-Fattah, H. Baumgart, G. Namkoong

2009 International Semiconductor Device Research Symposium, 2009

https://doi.org/10.1109/ISDRS.2009.5378124

R. Häusermann, E. Knapp, M. Moos, N. A. Reinke, T. Flatz, B. Ruhstaller

Journal of Applied Physics, 106, 104507-1-9, 2009

https://doi.org/10.1063/1.3259367

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T. Lanz, B. Perucco, D. Rezzonico, F. Müller, N. A. Reinke, R. Häusermann, B. Ruhstaller

Proceeding of the 4th European Photovoltaic Solar Energy Conference and Exhibition, Hamburg, Germany - Reference Number: 3BV.4.57, 2009.

https://dx.doi.org/10.4229/24thEUPVSEC2009-3BV.4.57

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Yueh-Tsung Tsai, Kensuke Goto, Osamu Yoshikawa, Shogo Mori, Takashi Sagawa and Susumu Yoshikawa

Japanese Journal of Applied Physics 50 (2011) 01BC13

https://dx.doi.org/10.1143/JJAP.50.01BC13

S. Wenger, S. Seyrling, A. N. Tiwari, M. Grätzel

Applied Physics Letters, 94, 173508-1-3, 2009

https://dx.doi.org/10.1063/1.3125432

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J. Frischeisen, C. Mayr, N.A. Reinke, S. Nowy, W. Brütting

Optics Express 16 (22), 8431-18436, 2008

https://doi.org/10.1364/OE.16.018426

B. Ruhstaller, T. Flatz, D. Rezzonico, M. Moos, N. Reinke, E. Huber, R. Häusermann, B. Perucco

Proceeding SPIE Photonics Conference, San Diego, Vol. 7051, 2008.

https://doi.org/10.1117/12.802447

Beat Ruhstaller, Thomas Flatz, Michael Moos, Guido Sartoris, Michael Kiy, Tilman Beierlein, Roland Kern, Carsten Winnewisser, Roger Pretot, Natalia Chebotareva, and Paul van der Schaaf

SID Symposium Digest of Technical Papers 38, 1686, 2007

https://doi.org/10.1889/1.2785649

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A. Köhnen, M.C. Gather, N. Riegel, P. Zacharias, K. Meerholz

Applied Physics Letters, 91, 113501-1-3, 2007

http://dx.doi.org/10.1063/1.2773930

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J.M. Leger, B. Ruhstaller, S.A. Carter

Journal of Applied Physics, 98 (12), 124907-1-7, (2005)

https://dx.doi.org/10.1063/1.2149162

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B. Ruhstaller, T.A. Beierlein, R. Gmür, S. Karg, H. Riel, G. Sartoris, H. Schwarzenbach, W. Riess

Proc. of the Conference on Simulation of Semiconductor Processes and Devices (SISPAD), 2.-4. Sept. 2004, (Editors: G. Wachutka, G. Schrag), Springer-Verlag, ISBN 3-211-22468-8, 2004.

https://link.springer.com/chapter/10.1007/978-3-7091-0624-2_37

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B. Ruhstaller, T.A. Beierlein, H. Riel, S. Karg, J.C. Scott, W. Riess

IEEE Journal of Selected Topics in Quantum Electronics, Optoelectronic Device Simulation, 9 (3), 723-31, 2003

https://doi.org/10.1109/JSTQE.2003.818852

J.M. Leger, S.A. Carter, B. Ruhstaller, H.-G. Nothofer, U. Scherf, H. Tillmann, H.-H. Hörhold

Physics Review B, 68, (5) 054209-054209, 2003

https://doi.org/10.1109/JSTQE.2003.818852

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T.A. Beierlein, B. Ruhstaller, D.J. Gundlach, H. Riel, S. Karg, C. Rost, W. Riess

Synthetic Metals, 138, 213-221, 2003

https://doi.org/10.1016/S0379-6779(02)01269-9

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H. Riel, S. Karg, T. Beierlein, W. Riess, K. Neyts

Journal of Applied Physics, 94 (8), 5290-5296, 2003

https://dx.doi.org/10.1063/1.1605256

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H. Riel, S. Karg, T.A. Beierlein, B. Ruhstaller, W. Riess

Applied Physics Letters, 82, 466-468, 2003

https://doi.org/10.1063/1.1537052

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B. Ruhstaller, S.A. Carter, S. Barth, H. Riel, W. Riess, J.C. Scott

Journal of Applied Physics, 89 (8), 4575-4586, 2001

https://doi.org/10.1063/1.1352027

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S. Barth, P. Muller, H. Riel, P. F. Seidler, W. Rieß, H. Vestweber, H. Bässler

Journal of Applied Physics, 89 (7), 3711-3719, 2001

https://dx.doi.org/10.1063/1.1330766

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B. Ruhstaller, P.J. Brock, J.C. Scott, U. Scherf, S.A. Carter

Chemical Physics Letters, 317, 238-244, 2000

https://doi.org/10.1016/S0009-2614(99)01390-1

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