Lin, M. Y., Li, Q.-T., & Li, Y.-L. (2024).

IEEE Photonics Technology Letters, 36, 1730–1733. https://doi.org/10.1109/LPT.2024.3450713

This study investigates the impact of black matrix (BM) width on the performance of quantum dot full-color displays. The authors use theoretical calculations and simulations to evaluate how BM width affects crosstalk, the aliasing effect, and color gamut. They find that increasing the BM width from 0 nm to 25 nm can eliminate crosstalk between subpixels and significantly reduce the aliasing effect. This leads to a substantial improvement in color gamut, with the display featuring an Ag/ZnO/Ag structure achieving a color gamut ratio of 100.65% Adobe RGB and a coverage of 87.17%. The study highlights the importance of BM width optimization in quantum dot display design for achieving high image quality and wide color gamut. This research is particularly relevant for applications like small panels and head-mounted displays.

How Setfos was used

Setfos was used to model and optimize all of the MIM (metal-insulator-metal) layer models and to calculate the transmitted spectrum for the subpixels with the MIM layer.

Simon J. Zeder, Balthasar Blülle, Beat Ruhstaller, and Urs Aeberhard,  Opt. Express 32, 34154-34171 (2024)

https://doi.org/10.1364/OE.522953

This paper presents a multiscale optical model developed to accurately quantify photon recycling (PR) and luminescent coupling (LC) in optoelectronic devices such as solar cells and LEDs. Photon recycling, the process of photon emission, re-absorption, and re-emission, can significantly enhance device efficiency, particularly in materials like GaAs, metal halide perovskites and even crystalline silicon. To accurately account for re-absorption effects, the model treats light absorption and emission equally, considering the full spectrum of internal modes within the device. This approach stands out from conventional methods, which focus solely on exterior-coupled modes.

The framework integrates two key propagation models: 

Coherent Wave-Optical Model: Applied to thin-film layers where light interference effects are significant, avoiding unphysical divergencies for emitters embedded in absorbing media and ensuring consistency with detailed balance principles. 

Incoherent Ray-Optical Model: Used for optically thick layers where coherence is lost, treating phase relations as irrelevant. 

The model also accounts for light scattering at textured surfaces, essential for devices like perovskite –silicon tandem solar cells. By merging these approaches, the paper provides a robust framework for computing local emission, re-absorption, and energy flux rates in devices with complex structures. Importantly, this allows for a detailed understanding of the impact of photon recycling on device performance, including enhanced external quantum efficiency (EQE) in LEDs and increased open-circuit voltages in solar cells. 

The model is validated through comparisons with analytical solutions, showing excellent agreement, and applied to a textured perovskite solar cell showcasing its capabilities. This validation confirms that the model can reliably be applied to real-world devices, offering a powerful tool for optimizing the performance of next-generation optoelectronic systems. 

Key Takeaways: 

∙ Comprehensive multiscale approach merging coherent and incoherent light models. 

∙ Applicability to complex textured devices like perovskite solar cells and LEDs. 

∙ Quantification of local re-absorption and energy flux rates. 

∙ Validation through comparison with analytical solutions. 

W.-H. Hu, F. Nüesch, D. Giavazzi, M. Jafarpour, R. Hany, M. Bauer, . Adv. Optical Mater. 2024, 12, 2302105. https://doi.org/10.1002/adom.202302105

This research focuses on using squaraine dyes in single-component shortwave infrared (SWIR) photodiodes and upconversion photodetectors. These devices achieve over 40% external quantum efficiency beyond 1000 nm through field-assisted exciton dissociation. By integrating SWIR photodiodes with organic LEDs, they convert SWIR photons into visible light, offering an alternative to inorganic imaging technologies.

Key Points

Efficient SWIR Detection: Over 40% external quantum efficiency beyond 1000 nm.

Field-Assisted Charge Generation: Enables efficient exciton dissociation.

Upconversion Photodetectors: Combine SWIR photodiodes with OLEDs for visible light emission.

Simplified Fabrication: Single-component layers enhance stability and reduce complexity.

Inorganic Alternative: Potential replacement for existing inorganic SWIR imaging technologies.

How Setfos Was Used

Setfos was employed for optical simulations, analyzing device layer properties using refractive index and extinction coefficient values. These simulations optimized light absorption and exciton generation, crucial for efficient SWIR detection and upconversion.

Cachafeiro, Miguel A Torre, Naresh Kumar Kumawat, Feng Gao and Wolfgang Tress.

National Science Review (2024): nwae128

https://doi.org/10.1093/nsr/nwae128

The paper investigates the pulsed operation of perovskite LEDs (PeLEDs), focusing on the role of mobile ions in transient electroluminescence. Drift-diffusion simulations demonstrate how mobile ions affect the TrEL signals and device performance, with findings crucial for optimizing PeLED design and function.

How Setfos was used

The Setfos software was used to perform drift-diffusion simulations that modeled the behavior of mobile ions in perovskite LEDs. It analyzed their impact on transient electroluminescence and device performance, helping to elucidate the mechanisms affecting light emission during pulsed operation.

A Boron, Nitrogen, and Oxygen Doped π-Extended Helical Pure Blue Multiresonant Thermally Activated Delayed Fluorescent Emitter for Organic Light Emitting Diodes That Shows Fast kRISC Without the Use of Heavy Atoms.

R. W. Weerasinghe, S. Madayanad Suresh, D. Hall, T. Matulaitis, A. M. Z. Slawin, S. Warriner, Y.-T. Lee, C.-Y. Chan, Y. Tsuchiya, E. Zysman-Colman, C. Adachi,

Adv. Mater. 2024, 2402289. https://doi.org/10.1002/adma.202402289

This study presents a boron, nitrogen, and oxygen-doped π-extended helical emitter for OLEDs that emits pure blue light efficiently without heavy metals. It demonstrates fast reverse intersystem crossing and high photoluminescence quantum yield, achieving narrow emission spectra close to the BT.2020 standard.

How Setfos was used

Setfos was used to analyze the orientation of transition dipole moments (TDM) within the films containing the MR-TADF emitter, f-DOABNA. This analysis is crucial for assessing how the TDM are oriented relative to the film surface, which affects the light outcoupling efficiency—a key factor in enhancing the performance of OLED devices.

Specifically, Setfos helped determine the horizontal-dipole ratios of f-DOABNA doped in different host materials. These ratios, varying between values indicative of perfectly horizontal to vertical orientation, provide insight into how efficiently the emitted light can be outcoupled from the OLED device. The results from Setfos showed that the emitter had a significant degree of horizontal alignment, especially in one host material, indicating better light outcoupling efficiency in that configuration.

C.-H. Chen, M.-H. Yu, Y.-Y. Wang, Y.-C. Tseng, I. Chao, I. Ni, B.-H. Lin, Y.-J. Lu, C.-C. Chueh,

Small 2024, 2307774.

https://doi.org/10.1002/smll.202307774

This paper presents a method to significantly enhance the performance of 2D tin-based red perovskite LEDs through the use of natural antioxidants and cyclic molecular additives, particularly ascorbic acid and 18-Crown-6. These additives mitigate the oxidation of Sn2+ to Sn4+ and improve film quality, leading to a substantial increase in external quantum efficiency (EQE), purer color, and better bias stability. The study showcases a potential dual-additive approach for advancing 2D Sn-based perovskite LEDs towards sustainability and efficiency.

How Paios was used

Paios was utilized for comprehensive electrical characterization, including space-charge-limited current measurements, electrochemical impedance spectroscopy, capacitance-voltage analysis, and transient electroluminescence studies. These tests revealed that the additives effectively reduced trap densities and leakage currents, improved carrier transport, and enhanced charge transfer efficiency, corroborating the additives' impact on device performance and stability.

T. Lee, M. Lee, K. Kim, H. Lee, S.-Y. Yoon, H. Yang, S. Yu, J. Kwak, Adv. Optical Mater. 2024, 2302509.

https://doi.org/10.1002/adom.202302509

This study presents angle-independent top-emitting quantum dot light-emitting diodes (QLEDs) featuring a solution-processed subwavelength scattering–capping layer (SCPL) composed of ZnO nanoparticles. This SCPL enhances light extraction and minimizes angle-dependent color shifts, achieving a 44% improvement in external quantum efficiency without perceivable spectral shifts across viewing angles. The dual functionality of the SCPL, serving both as a capping and scattering layer, introduces a simplified, cost-effective method for fabricating high-performance, angle-stable QLED displays.

How Setfos was used

Setfos was utilized to optimize the microcavity structure of blue-emitting QLEDs by adjusting the thickness of hole transport and electron transport layers, aiming for maximum light extraction efficiency and luminance. The tool's simulations guided the experimental verification of the device's optoelectronic performance, helping to achieve superior efficiency and color stability by precisely controlling the thickness of the scattering–capping layer (SCPL).

E. Benvenuti, A. Lanfranchi, S. Moschetto, M. Natali, M. Angelini, P. Lova, F. Prescimone, V. Ragona, D. Comoretto, M. Prosa, M. Bolognesi and S. Toffanin,

J. Mater. Chem. C, 2024,

DOI: 10.1039/D3TC04321E.

This paper presents the development of an all-organic, on-chip integrated system for fluorescence detection, combining organic photodiodes (OPDs), organic light-emitting diodes (OLEDs), and a polymeric distributed Bragg reflector (DBR) filter. By integrating these components on a single substrate, the system offers a compact and efficient solution for fluorescence sensing, which is crucial for applications ranging from food safety to environmental monitoring. The use of organic materials allows for low-cost, flexible sensors that can be easily produced and deployed. The paper demonstrates that this integrated approach significantly enhances the optical efficiency and sensitivity of the fluorescence sensor, making it capable of detecting concentrations as low as 9.2 μM of the model dye Rhodamine 700. This advancement represents a significant step towards the development of portable, high-performance sensors for point-of-need applications​

How Sefos was used

Setfos was used to design the OLED structure to achieve an efficient and narrow phosphorescent emission, crucial for the integrated fluorescence sensor's performance. The simulation helped in fine-tuning the composition and thickness of the OLED's interlayers, including an organic index matching layer, to enhance light extraction and emission characteristics tailored to the absorption spectrum of the fluorescent dye, Rhodamine 700.

Xu, Ting and Jiang, Haixiao and Dong, Haojie and Zhao, Kele and Liang, Xiao and Sun, Yanqiu and Ding, Lei and meng, lingqiang and Meng, Hong,

Available at SSRN: https://ssrn.com/abstract=4610784

The study presents a novel approach to enhance blue MR-TADF OLEDs' efficiency and color purity using tandem device structures. By employing TBN-TPA as the blue MR-TADF material in tandem OLED devices, narrow-band emission and high color purity were achieved through optical interference and microcavity effects, aligning with BT 2020 standards. This advancement underscores the potential of tandem architectures and MR-TADF emitters in developing high-performance OLEDs with both high efficiency and wide color gamut, suggesting further research in optimizing tandem structures and MR-TADF materials.

How Setfos was used

Setfos software was utilized to simulate optical and electrical characteristics of OLED devices, particularly analyzing spectral enhancements, microcavity effects, and interference within the tandem OLED structures, to predict and understand device performance improvements, including color purity and efficiency.

C.-H. Chen, M.-H. Yu, Y.-Y. Wang, Y.-C. Tseng, I. Chao, I. Ni, B.-H. Lin, Y.-J. Lu, C.-C. Chueh,

Small 2024, 2307774.

https://doi.org/10.1002/smll.202307774

This research explores the use of natural antioxidants as additives to improve the fabrication of environmentally friendly Sn-based perovskite films, tackling oxidation and crystallization challenges. Ascorbic acid is highlighted for its effectiveness against oxidation, and when combined with 18-Crown-6, it enhances 2D red Sn-based PeLED performance, increasing efficiency, color purity, and stability, showcasing a sustainable dual-additive approach for optoelectronic applications.

How Paios was used

Impedance and TEL to demonstrate better transport with additives.

Elkhouly, K., Goldberg, I., Zhang, X. et al.

Nat. Photon. (2024).

https://doi.org/10.1038/s41566-023-01341-7

Imec's research, published in Nature Photonics, details the creation of a perovskite LED stack that dramatically outshines conventional OLEDs.

The team used Setfos to analyze and optimize the light interactions within the perovskite structure. This approach significantly enhanced the LED's brightness and efficiency. The breakthrough paves the way for high-intensity, thin-film perovskite lasers with potential applications in medical diagnostics, environmental sensing, and advanced imaging, heralding a new era in optoelectronic devices. Setfos was instrumental in achieving the precise architecture needed for this revolutionary leap in light-emitting technology.

Li, Z., Chen, Z., Shi, Z. et al. Nat Commun 14, 6441 (2023). https://doi.org/10.1038/s41467-023-41929-9

This paper focuses on enhancing the performance and response speed of perovskite light-emitting diodes (PeLEDs) by engineering the charge injection at the organic-inorganic heterointerfaces. They introduced a self-assembled monolayer to improve interface robustness, passivate interfacial traps, and align energy levels.

How Paios was used

Paios was used to study the transient photo-voltage and photocurrent responses, revealing improved charge injection and transport properties, which significantly enhanced the device's efficiency and response speed.

Zhang, T., Zhao, F., Liu, P., Tan, Y., Xiao, X., Wang, Z., Wang, W., Wu, D., Sun, X.W., Hao, J., Xing, G. and Wang, K. (2023)

Adv. Photonics Res., 4: 2300146.

https://doi.org/10.1002/adpr.202300146

The paper investigates electron leakage in green InP Quantum-Dot Light-Emitting Diodes (QLEDs), causing carrier imbalance and reduced efficiency. It identifies the Fermi energy difference between green InP/ZnS Quantum Dots and the ITO anode as the main cause.

How Setfos was used

Setfos was used for electrical simulations of recombination rates, helping to understand electron leakage paths and the impact of an ultrathin LiF layer, which ultimately improves device performance by enhancing electron confinement and hole injection.

S. Sasaki, K. Goushi, M. Mamada, S. Miyazaki, K. Miyata, K. Onda, C. Adach Adv. Optical Mater. 2023, 2301924. https://doi.org/10.1002/adom.202301924

The paper explores intramolecular triplet–triplet annihilation (TTU) upconversion in organic light-emitting diodes (OLEDs) for enhanced electroluminescence efficiency. The study focuses on the intramolecular TTU of anthracene dimers in OLEDs, showing improved electroluminescence efficiency under low dopant concentrations.

How Setfos was used

Setfos was utilized to estimate the out-coupling efficiency of the OLEDs, contributing to the understanding of the TTU process and device optimization.

Q. Wang, H. Zhu, Y. Tan, J. Hao, T. Ye, H. Tang, Z. Wang, J. Ma, J. Sun, T. Zhang, F. Zheng, W. Zhang, H. W. Choi, W. C. H. Choy, D. Wu, X. W. Sun, K. Wang. Adv. Mater. 2023, 2305604.

https://doi.org/10.1002/adma.202305604

The paper demonstrates a spin quantum dot light-emitting diode (spin-QLED) using 2D chiral perovskite as a spin injection layer based on the chiral-induced spin selectivity (CISS) effect, enabling spin-dependent carrier transport. It operates at room temperature and zero magnetic field, achieving circularly polarized electroluminescence (CP-EL) with an asymmetric factor of 1.6 × 10^-2. The work highlights the potential of chiral materials in spintronics and quantum-based devices.

How Setfos was used

Setfos simulation was used to analyze the recombination center and carrier recombination rate distribution in the device, providing insights into the performance and guiding future improvements.

Qi Dong, Liping Zhu, Shichen Yin, Lei Lei, Kenan Gundogdu, and Franky So

ACS Photonics 2023 10 (9), 3342-3349

DOI: 10.1021/acsphotonics.3c00812

Researchers have developed a highly efficient linearly polarized organic LED, capitalizing on the inherent polarization properties of the transverse electric waveguide mode within the device. Utilizing a linear grating, they achieved 67.6% light confinement in this mode, resulting in a polarized LED with a current efficiency of 136 cd/A and a polarization ratio exceeding 30. Further enhancements to current efficiency are possible, making this architecture adaptable for various thin-film LED applications in photonics.

How Setfos was used

The researchers used Setfos for optical simulations to analyze the spatial distribution of different modes in the top-emitting OLED device, determine the optimized device geometry, and simulate the dissipated power versus the effective refractive index in the optimized condition to enhance the efficiency of polarized emission.

Binh Minh Nguyen, Markus Schmid, Johann Kirsch, Albin Cakaj, and Wolfgang Brütting

Chemistry of Materials 2023 35 (17), 7333-7343

DOI: 10.1021/acs.chemmater.3c01804

The research explores how four nonpolar dyes orient within neat films and doped guest-host systems in organic light-emitting diodes (OLEDs). It identifies shape anisotropy and the relationship between the substrate temperature during deposition and the system's glass transition temperature (Tg) as critical to the alignment of emissive transition dipoles. Notably, in mixed cohost systems with components of differing Tgs, the alignment may not align with the mixed host's effective Tg. The study also proposes using a molecule's principal moments of inertia to assess its reorientation resilience and aspect ratio to gauge shape anisotropy.

How Phelos was used

Angular-Dependent Photoluminescence measurements were performed with Phelos.

Hye In Yang, Nagarjuna Naik Mude, Jin Young Kim, Jun Hyeog Oh, Ramchandra Pode, and Jang Hyuk Kwon,

Opt. Express 31, 18407-18419 (2023)

https://doi.org/10.1364/OE.487301

The study presents an enhanced top emission OLED (TEOLED) device structure that significantly improves light extraction, specifically by addressing waveguide mode loss in the thin film encapsulation (TFE) layer. By introducing a low refractive index (RI) layer between the capping layer (CPL) and the aluminum oxide (Al2O3) layer, the device manipulates evanescent waves to redirect trapped light within the device, increasing its extraction. This novel TFE structure (CPL/low RI layer/Al2O3/polymer/Al2O3) led to a 23% increase in current efficiency and a 26% enhancement in the blue index value for the blue TEOLED device. This method shows significant potential for advancing flexible optoelectronic device encapsulation technologies.

How Setfos was used

SETFOS 5.1 is used as an optical simulator. The RI of the glass substrate, indium tin oxide (ITO), and organic layers are taken as ∼1.5, 1.8∼2.0, and ∼1.8, respectively. The RI and extinction coefficient of silver (Ag) and magnesium (Mg):Ag (10:1) used as an anode and cathode, respectively, are taken from the reported values. For the EML, the thin film photoluminescence spectrum of 2,12-di-tert-butyl-N,N,5,9-tetrakis(4-(tert-butyl)phenyl)-5,9-dihydro-5,9-diaza-13bboranaphtho[ 3,2,1-de]anthracen-7-amine (DABNA-NP-TB) for the blue TEOLED device, bis[2- (2-pyridinyl-N)phenyl-C](acetylacetonato)iridium(III) for the green TEOLED device, and (bis(4- methyl-2-(3,5-dimethylphenyl)quinoline))Ir(III (tetramethylheptadionate) for the red TEOLED device are used.

Dian Luo, Wei-Yu Chen, Wei-Lun Syu, Shun-Wei Liu, and Chih-Hao Chang

ACS Photonics 2023 10 (8), 2874-2885

DOI: 10.1021/acsphotonics.3c00590

The study introduces four innovative design strategies for tandem organic light-emitting diodes (TOLEDs) to overcome the efficiency loss caused by charge-generation layer (CGL) interactions in multi-layer devices. The designs include an optimized CGL, an exciplex host in the emitting layer for improved carrier balance and reduced voltage, simplified architecture, and nanoparticle diffusers. These led to a three-stacked TOLED reaching 78.7% efficiency, 2.5 times higher than conventional devices. Adding a nanoparticle diffuser further increased efficiency to 123.9%, with a record luminance of 411,531 cd/m². The findings show promise for TOLEDs in OLED phototherapy and display applications with high efficiency and luminance.

How Setfos was used

Setfoswas chosen as the calculation tool for the external optical coupling of the devices.

Luo, D., Hou, M.-C., Wang, K.-Y., Chang, C.-H., Liu, S.-W., Lu, C.-W. and Su, H.-C. (2023),

Adv. Mater. Technol., 8: 2300563. https://doi.org/10.1002/admt.202300563

The research presents a tandem white OLED/LEC hybrid device, combining a red OLED and a blue LEC, which simplifies fabrication compared to multi-layered OLEDs. The device includes a charge-generating layer (CGL) that not only links the two, but also improves carrier balance, leading to an external quantum efficiency (EQE) of 21.53%. Efficiency jumps to 37.88% when using a diffusive substrate. This demonstrates a simpler yet highly efficient structure, offering promising potential for cost-effective lighting solutions.

How Setfos was used

To clarify the relationship between the recombination zone position and the optical mode distribution for Device B, Device R, and Device T. The optical simulation software Setfos was employed as the analysis tool as was the optical mode distribution of the devices.

Yan-Yun Jing et al. ,Sci.Adv.9, eadh8296(2023). DOI:10.1126/sciadv.adh8296

Here the researchers have developed a new strategy to create red Multiple Resonance (MR) emitters for OLEDs achieves high efficiency and color purity by adjusting the π-conjugation and electron-donating properties within a boron-based structure. The result is a range of emissions with narrow bandwidths and a particularly pure-red device meeting the BT.2020 standard with high quantum efficiency and brightness. This approach suggests a promising direction for developing OLED materials with superior color performance.

How Setfos was used

The experimental EQEs closely aligned with the theoretical efficiencies predicted by optical simulations using Setfos software (33.6% for CzIDBNO and 27.9% for IDIDBNO), which further demonstrated the intricate interplay of these parameters on outcoupling efficiency and overall device performance.

Yu Zhang, Weiqing Nie, Mengli Hu, Wu Liu, Heng Liu, Xiaomin Huo, Yao Lu, Dandan Song, Bo Qiao, Zhiqin Liang, Zhiqiang Jiao, Zheng Xu, Guangcai Yuan, and Suling Zhao

ACS Photonics 2023 10 (10), 3521-3530

https://doi.org/10.1021/acsphotonics.3c00524

This research outlines the advancement in tandem optoelectronic devices, specifically a perovskite/organic quasi-tandem system for narrowband photodetectors (NPDs) targeting the visible to near-infrared spectrum. By varying the composition of perovskite and organic layers, the spectral response is tunable, enhancing device selectivity and flexibility. Achieving a peak response near 790 nm with a 41 nm bandwidth, these NPDs exhibit rapid submicrosecond response times, significantly outperforming traditional thick-layer photodetectors, marking a step forward in the development of ultra-fast NPDs.

How Setfos was used

Setfos was utilized to stimulate the penetration of different monochromatic light, the thickness of perovskite (MAPbI3) was set as 1700 nm, and a 150 nm of organic blend layer (PM6:IT-4F) was set on the perovskite. Take thickness as the scanning parameter, with a step size of 10 nm. The optical parameters (n, k) of the materials are obtained through an ellipsometer.

Noel C. Giebink and Stephen R. Forrest

Phys. Rev. Lett. 130, 267002 – Published 29 June 2023

https://doi.org/10.1103/PhysRevLett.130.267002

The study establishes a thermodynamic limit for OLED efficiency, revealing that OLEDs require higher voltage for the same brightness compared to inorganic LEDs due to strong exciton binding. Optimizing factors like low exciton binding energy, long exciton lifetime, and efficient electron-hole recombination can minimize OLED overpotential, suggesting top-performing OLEDs may be near their efficiency limit. This framework aids in developing low-voltage OLEDs for displays and lighting.

How Setfos was used

Setfos was used to validate the theoretical model considering also exciton dissociation.

Jinno, H., Shivarudraiah, S. B., Asbjörn, R., Vagli, G., Marcato, T., Eickemeyer, F. T., Pfeifer, L., Yokota, T., Someya, T., Shih, C.-J.,

. Adv. Mater. 2023, 2304604.

https://doi.org/10.1002/adma.202304604

This research presents a breakthrough in ultrathin, flexible skin optoelectronics for Internet of Things (IoT) applications. Traditional issues like underperformance due to low polymer process temperatures and spectral distortion from bending are overcome using solution-processed perovskite semiconductors. The study introduces high-efficiency perovskite solar cells and LEDs on polymer films with exceptional thermal stability, achieving record efficiencies (18.2% for solar cells, 15.2 cd A−1 for LEDs) and bending-resistant light emission. This advancement enables reliable, high-performance, self-powered wearables and IoT sensors, demonstrating practical applications such as accurate pulse monitoring at a high selectivity rate.

How Setfos Was used

Finite element analysis for ultraflexible LED was simulated with the Setfos emission module. By expecting the dipole emission model of LED, the module allows to deliver emission spectra of ultraflexible LED with different angle.

Kang, H., Hwang, Y., Kang, Cm. et al.

Sci Rep 13, 14070 (2023).

https://doi.org/10.1038/s41598-023-41033-4

This research explores electrical crosstalk in high-resolution OLED microdisplays impacting color distortion, especially in AR/VR applications. Through simulations and experimental measures, it was found that decreasing sheet resistance in the common organic layer elevated crosstalk, and increasing pixel density led to a color gamut reduction.

How Laoss Simulation was used

Simulation process. Commercial software LAOSS (Fluxim) which used 2 + 1D finite element model based on the conductivity of the common layer17,18 and J–V–L characteristics of the fabricated white OLED were used for the electrical crosstalk calculation.

Dr. Camilla Arietta VAEL-GARN

Ph. D Thesis, EPFL , 12 Sept. 2023

https://doi.org/10.5075/epfl-thesis-10350

The study explores polymeric semiconductors in organic electronics, using drift-diffusion simulation to study three areas. First, the applicability of thermally stimulated current measurement for studying trap states in organic semiconductors is investigated, identifying a reliable formula for data analysis. Second, reversible trap states in a polymeric light-emitting diode are studied, suggesting trap state formation and disaggregation may involve water and oxygen molecules. Lastly, the operational principles of an upconverter device converting near infra-red to visible light are examined, finding that electron mobility in the emission layer significantly affects the device's response time.

Han Bin Cho, Ju Yeon Han, Ha Jun Kim, Noolu Srinivasa Manikanta Viswanath, Yong Min Park, Jeong Wan Min, Sung Woo Jang, Heesun Yang, and Won Bin Im

ACS Appl. Mater. Interfaces 2023, 15, 24, 29259–29266, June 8, 2023

https://doi.org/10.1021/acsami.3c02857

Quantum dot light-emitting diodes (QLEDs) often use PEDOT:PSS as a hole injection layer (HIL), but it has a high energy barrier for hole injection, resulting in low efficiency. Researchers improved device efficiency by using a bilayer HIL with VO2 and PEDOT:PSS, achieving an 18% external quantum efficiency, 78 cd/A current efficiency, and 25,771 cd/m² maximum luminance, compared to 13%, 54 cd/A, and 14,817 cd/m² for the PEDOT:PSS-based QLED. This approach effectively reduced the energy barrier between indium tin oxide (ITO) and PEDOT:PSS, boosting QLED efficiency.

How Setfos was used

The optical simulation was conducted using the advanced simulation software Setfos.

Li, G., Pu, J., Yang, Z., Deng, H., Liu, Y., Mao, Z., Zhao, J., Su, S., Chi, Z., Aggregate 2023, 00, e382.

https://doi.org/10.1002/agt2.382

This study proposes a design strategy for constructing highly efficient organic light-emitting diodes (OLEDs) using thermally activated delayed fluorescence (TADF) emitters with high horizontal dipole ratios. The researchers designed two TADF emitters, BO-3DMAC and BO-3DPAC, using a shamrock-shaped structure. These emitters exhibited high horizontal dipole ratios of 84-93% in both neat and doped films. The emitters showed excellent external quantum efficiencies (EQEs) of up to 38.7% in doped OLEDs with sky-blue emission. The researchers also demonstrated that the shamrock-shaped design resulted in aggregation-induced emission (AIE) and low efficiency roll-off. The emitters had low singlet-triplet energy splitting (ΔEst) and achieved high PLQYs. The results highlight the potential of the shamrock-shaped design to construct TADF emitters with high Θ// and pave the way for the development of high-performance OLEDs.

How Setfos was used

The refractive index of the materials were extracted from the Setfos database and the light out-coupling efficiency of devices were also simulated.

Wang, J, Xie, M, Pang, H, Zhang, C, Sang, M, Zhang, Q, et al.

J Soc Inf Display. 2023; 31( 6): 457– 465.

https://doi.org/10.1002/jsid.1205

This scientific article discusses the development of high-performance red and green phosphorescent emitters suitable for the BT.2020 color gamut in displays. The researchers conducted optical simulations to determine the optimal spectra for the emitters. For the green emitter, they found that a spectrum with a peak wavelength at 526 nm and a full width at half maximum (FWHM) less than 30 nm could achieve the desired color coordinates. For the red emitter, they discovered that decreasing the FWHM instead of red-shifting the spectrum was important to achieve the desired color coordinates while maintaining high current efficiency. Based on these simulation results, the researchers designed and synthesized novel deep green (DGD) and deep red phosphorescent (DRD-II) emitters. The DGD emitter achieved a color coordinate of (0.170, 0.777) with a current efficiency of 171 cd/A, and the DRD-II emitter achieved a color coordinate of (0.708, 0.292) with a current efficiency of 59 cd/A. The researchers also demonstrated that the angular dependence of these devices was comparable to those with commercial emitters. Overall, these findings suggest that phosphorescent emitters have the potential to meet the BT.2020 color standard in organic displays.

How was Setfos used?

SETFOS 5.0 was used for optical simulations to determine the optimal spectrum of a green emitter suitable for BT.2020. The simulations involved employing a series of simulated green photoluminescence (PL) spectra. Optical constants, such as the refractive index and the extinction coefficient of each emitter, were taken into account during the simulations.

Kamijo, T., van Breemen, A.J.J.M., Ma, X. et al. A touchless user interface based on a near-infrared-sensitive transparent optical imager. Nat Electron (2023).

https://doi.org/10.1038/s41928-023-00970-8

Researchers have developed a touchless user interface based on a visually transparent near-infrared-sensitive organic photodetector (OPD) array. The touchless interface can be used on top of a display, eliminating the need for physical contact.

The OPD array is designed with optical transparency in mind, using printed copper grids and patterned organic photodetector subpixels. The design optimization results in a high photodetectivity of 10^12 Jones at 850 nm and a visible-light transmittance of 70%.

The touchless user interface can be used with a penlight or through gesture recognition, providing a hygienic and convenient alternative to traditional touch screens. The technology has potential applications in automated teller machines (ATMs), ticket vending machines, and kiosks, where hygiene is a concern. It is a scalable and flexible solution that can be integrated into a variety of display applications without size limitations or calibration requirements. 2D FEM simulations for the surface potential and the current density distributions derived from the printed Cu grid structure .

How Fluxim’s Research Tools were used

Setfos

Numerical electro-optical simulations for the photogenerated J–V curves of our NIR-sensitive OPDs were performed by using Setfos.

The VLT of the parallel OPD subpixel array was calculated by the summation of the simulated optical transmittance for each component using Setfos

Laoss

2D FEM simulations for the surface potential and the current density distributions derived from the printed Cu grid structure for our NIR-sensitive OPDs were performed by Laoss 4.0