Article
Optics
Longheng Qi, Peian Li, Xu Zhang, Ka Ming Wong, Kei May Lau
Summary: A prototype of full-color micro-LED micro-display with a pixel density of 391 ppi is demonstrated using InGaN/AlGaInP heterogeneous integration. This display shows the feasibility and prospects of high brightness, good color performance, and high-resolution micro-LED micro-displays in future metaverse applications.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Optics
Jinpeng Huang, Zelin Hu, Xiang Gao, Yi Xu, Liancheng Wang
Summary: This study proposes a single-chip micro-LED display technology with unidirectional emission through the integration of a resonant cavity and metasurface, which can achieve efficient naked-eye 3D display with a wide viewing angle and multiple viewpoints. The research promotes the application of GaN-based micro-LEDs in displays, especially in 3D displays.
Article
Optics
Meng Tian, Huabin Yu, Muhammad Hunain Memon, Zhanyong Xing, Chen Huang, Hongfeng Jia, Haochen Zhang, Danhao Wang, Shi Fang, Haiding Sun
Summary: Micro-LEDs with smaller inclined chip sidewall angles exhibit improved external quantum efficiency due to stronger reflection of the inclined sidewall, leading to enhanced light extraction efficiency. The EQE improvement by adopting an inclined sidewall is more significant as the diameter of the LED chip reduces. Numerical optical modeling further verifies the impact of sidewall angles on the light extraction efficiency of micro-LEDs.
Article
Chemistry, Multidisciplinary
Biao Zhao, Huanyu Ma, Haoran Jia, Mengyun Zheng, Kunxiang Xu, Runnan Yu, Songnan Qu, Zhan'ao Tan
Summary: Two types of triphenylamine-derived solid-state emissive carbon dots (CDs) are synthesized through solvothermal treatment, exhibiting orange and yellow color. The nonplanar structure and good carrier mobility of the triphenylamine unit effectively inhibit the direct pi-pi stacking and enhance the fluorescence properties of the CDs in aggregation state. Using the CDs as single emissive layer, high-performance orange and green electroluminescent light-emitting diodes (LEDs) are fabricated, achieving high brightness, current efficiency, and low turn-on voltage. This work provides a versatile platform for the construction of novel solid-state emissive CDs with potential applications in photoelectric devices.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Optics
Longheng Qi, Xu Zhang, Wing Cheung Chong, Peian Li, Kei May Lau
Summary: This paper describes the fabrication processes of a high-brightness micro-LED display using GaN-on-Si epi-wafers, showcasing high resolution and excellent performance. The Si growth substrate was removed using wet etching, and optical crosstalk was mitigated through design and process modifications.
Article
Automation & Control Systems
Jean S. Brand, Guirguis Z. Abdelmessih, J. Marcos Alonso, Yijie Wang, Yueshi Guan, Marco A. Dalla Costa
Summary: This article provides a detailed analysis of low-frequency ripple transfer in integrated two-stage power converters, offering a design methodology for optimal power control selection and bulk capacitance reduction. Through a case study, it is shown that replacing a boost converter with a buck-boost converter can significantly reduce bus capacitance.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2021)
Article
Multidisciplinary Sciences
Juan Francisco Gonzalez Marin, Dmitrii Unuchek, Zhe Sun, Cheol Yeon Cheon, Fedele Tagarelli, Kenji Watanabe, Takashi Taniguchi, Andras Kis
Summary: In this study, the authors demonstrate the electrical control of emission angle and polarization of light emitted from a 2D LED based on WSe2 at room temperature. This finding showcases the potential of 2D semiconductors as compact, fast, and tunable light sources, and is significant for the realization of electrically driven polariton lasers.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Yu Xiao, Wenge Xiao, Dan Wu, Linquan Guan, Min Luo, Ling-Dong Sun
Summary: The study has successfully designed an extra-broadband VIS-NIR emitting phosphor capable of emitting light from 460nm to 880nm upon 450nm excitation, with efficient energy transfer and potential applications in multifunctional LED devices.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Li Liu, Qingqing Feng, Yu Zhang, Xiaolu Zhu, Lanli Chen, Zhihua Xiong
Summary: Improving the luminescence efficiency of long wavelength InGaN-based LEDs is a challenging task, and strain-induced piezoelectric effect has been shown to be an effective measure. Reduction of valence band offset at InGaN/GaN heterointerfaces significantly improves hole injection. Tensile strain in the GaN film on a silicon substrate increases the overlap of electron and hole wave functions, leading to enhanced efficiency. Control of the strain-induced piezoelectric polarisation of the InGaN quantum well layer further improves the internal quantum efficiency.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Multidisciplinary Sciences
Shofu Matsuda, Chikara Itagaki, Kyoya Tatsuguchi, Masamichi Ito, Hiroto Sasaki, Minoru Umeda
Summary: This study investigates the effect of Au/fullerene-doped TPA interface on efficient hole injection, finding that using C-70 as a dopant can significantly reduce the hole injection barrier. The ion-dipole interaction between TPA and fullerenes is considered to play a role in reducing the barrier height based on cyclic voltammetry.
SCIENTIFIC REPORTS
(2022)
Article
Chemistry, Multidisciplinary
Zitang Wei, Kang Wang, Wenchao Zhao, Yao Gao, Qixuan Hu, Ke Chen, Letian Dou
Summary: By synthesizing and incorporating a novel selenophene-containing organic ligand STm into a Sn(ii)-based two-dimensional perovskite, the band offset can be fine-tuned, resulting in high performance and enhanced operational stability in field-effect transistor and light-emitting diode devices.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Chung Hyeon Jang, Ye In Kim, Amit Kumar Harit, Jung Min Ha, Sejeong Park, Young Wook Noh, Ah-young Lee, Kyeong Su Kim, Jae Woong Jung, Han Young Woo, Myoung Hoon Song
Summary: This study reports highly efficient green-emitting PeLEDs by introducing semiconducting molecular additives (Fl-OEGA and Fl-C8A). The conjugated additives exist primarily at the grain boundaries of perovskite, reducing the contact potential difference and residual tensile stress. The PeLEDs with Fl-OEGA show minimal shift in turn-on voltage and less decrease in current density compared to devices with insulating EDEA. Furthermore, the 3D CsPbBr3-PeLEDs achieve the highest external quantum efficiency of 21.3% with the incorporation of semiconducting Fl-OEGA as a new multifunctional additive.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Applied
Ramanaskanda Braveenth, Kanthasamy Raagulan, Lee Ro Lee, Keunhwa Kim, Young Hee Park, Su Bin Oh, Ji Sun Lee, Il-Ji Bae, Bo Mi Kim, Minyoung Kim, Kyu Yun Chai
Summary: Fluorene-based molecules are widely used in organic light emitting diodes (OLEDs). Two new materials, FLU-DTPA and FLU-DCAR, were designed and synthesized for OLED applications. The FLU-DCAR based yellow phosphorescent device showed high current and external quantum efficiencies, outperforming the triphenylamine-based FLU-DTPA. Additionally, non-doped fluorescent devices fabricated with the newly synthesized molecules exhibited deep blue emission.
Article
Optics
Jinlong Piao, Junhua Wu, Ziqi Ye, Hao Zhang, Jinjia Li, Pengzhan Liu, Hao Wang, Ziping Cao, Yongjin Wang
Summary: In this study, a monolithic integration of a metal oxide semiconductor field effect phototransistor and a light-emitting diode on a GaN-on-Si LED epitaxial wafer was achieved. The integrated device showed promising performance as a UV detector and had potential applications in visible light communication.
Article
Chemistry, Inorganic & Nuclear
Jiutian Wang, Lihong Jiang, Ran Pang, Su Zhang, Da Li, Kai Li, Chengyu Li, Hongjie Zhang
Summary: In this study, a novel near-infrared phosphor with a single emitting center was successfully synthesized, showing broadband emission characteristics. The relationship between the local coordination environment and the crystal structure on the luminescence properties was analyzed. This research provides important insights for the design and development of super broadband near-infrared phosphors.
INORGANIC CHEMISTRY FRONTIERS
(2022)
