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Shi J, Wang Y, Yan X, Li Z, Tangdiongga E. Coverage extended MMF-based indoor OWC using overfilled launch and diversity reception. OPTICS LETTERS 2024; 49:1567-1570. [PMID: 38489452 DOI: 10.1364/ol.512452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 02/20/2024] [Indexed: 03/17/2024]
Abstract
Speckle patterns generated as coherent optical beams are reflected by scattering elements. Multimode fibers (MMFs) can modify the transverse intensity distribution of speckle patterns with macro perturbations, i.e., pressures, providing a simple and low-cost way to achieve equivalent beam-steering for indoor optical wireless communications (OWCs) with divergent optical beams. However, the received optical power (ROP) variance severely limits the mobility of user terminals. In this paper, the issue is alleviated by using the overfilled launch of MMFs and the diversity gain of multi-receivers. By adjusting the axial spatial coupling distance between the MMF and the single mode fiber (SMF) emitting coherent laser, the number of excited modes of MMF can be significantly increased at 1550 nm with negligible coupling and bending losses. In addition, the signal-to-noise ratio (SNR) enhancement obtained by applying two receivers is theoretically analyzed for the case when either thermal noise or shot noise is dominant. The experimental results demonstrate that the proposed scheme can efficiently compensate for the ROP inhomogeneity, and at the same time it can extend the achievable full steering angle up to 12° at a 1.5-m free-space distance for bit error rate (BER) values of less than 3.8 × 10-3.
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2
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Zhang S, He R, Duo Y, Chen R, Wang L, Wang J, Wei T. Plasmon-enhanced deep ultraviolet Micro-LED arrays for solar-blind communications. OPTICS LETTERS 2023; 48:3841-3844. [PMID: 37527063 DOI: 10.1364/ol.496397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 06/19/2023] [Indexed: 08/03/2023]
Abstract
Localized surface plasmon resonance (LSPR)-enhanced deep ultraviolet (DUV) Micro-light emitting diodes (Micro-LEDs) using Al nanotriangle arrays (NTAs) are reported for improving the -3 dB modulation bandwidth. Through self-assembled nanospheres, the high-density Al NTAs arrays are transferred into the designated p-AlGaN region of the Micro-LEDs, realizing the effect of LSPR coupling. A 2.5-fold enhancement in photoluminescence (PL) intensity is demonstrated. Combined with the PL intensity ratio at 300 K and 10 K, internal quantum efficiency (IQE) may be increased about 15-20% by the plasmonic effect and the carrier lifetime decreases from 1.15 ns to 0.82 ns, suggesting that LSPR accelerates the spontaneous emission rate. Resulting from the improvement of the IQE, the electroluminescence intensity of Micro-LED arrays with LSPR is obviously increased. Meanwhile, the -3 dB bandwidth of 6 × 6 Micro-LED arrays is increased from 180 MHz to 300 MHz at a current density of 200 A/cm2. A potential way is proposed to further increase both the IQE and the modulation bandwidth of DUV Micro-LEDs.
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3
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Wang JX, Wang Y, Almalki M, Yin J, Shekhah O, Jia J, Gutiérrez-Arzaluz L, Cheng Y, Alkhazragi O, Maka VK, Ng TK, Bakr OM, Ooi BS, Eddaoudi M, Mohammed OF. Engineering Metal-Organic Frameworks with Tunable Colors for High-Performance Wireless Communication. J Am Chem Soc 2023. [PMID: 37421307 DOI: 10.1021/jacs.3c03672] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2023]
Abstract
Metal-organic frameworks (MOFs) have emerged as excellent platforms possessing tunable and controllable optical behaviors that are essential in high-speed and multichannel data transmission in optical wireless communications (OWCs). Here, we demonstrate a novel approach to achieving a tunable wide modulation bandwidth and high net data rate by engineering a combination of organic linkers and metal clusters in MOFs. More specifically, two organic linkers of different emission colors, but equal molecular length and connectivity, are successfully coordinated by zirconium and hafnium oxy-hydroxy clusters to form the desired MOF structures. The precise change in the interactions between these different organic linkers and metal clusters enables control over fluorescence efficiency and excited state lifetime, leading to a tunable modulation bandwidth from 62.1 to 150.0 MHz and a net data rate from 303 to 363 Mb/s. The fabricated color converter MOFs display outstanding performance that competes, and in some instances surpasses, those of conventional materials commonly used in light converter devices. Moreover, these MOFs show high practicality in color-pure wavelength-division multiplexing (WDM), which significantly improved the data transmission link capacity and security by the contemporary combining of two different data signals in the same path. This work highlights the potential of engineered MOFs as a game-changer in OWCs, with significant implications for future high-speed and secure data transmission.
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Affiliation(s)
- Jian-Xin Wang
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Yue Wang
- Photonics Laboratory, Division of Computer, Electrical, and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Maram Almalki
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Jun Yin
- Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon 999077, Hong Kong, P. R. China
| | - Osama Shekhah
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Jiangtao Jia
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Luis Gutiérrez-Arzaluz
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
- KAUST Catalysis Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Youdong Cheng
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Omar Alkhazragi
- Photonics Laboratory, Division of Computer, Electrical, and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Vijay K Maka
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Tien Khee Ng
- Photonics Laboratory, Division of Computer, Electrical, and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Osman M Bakr
- KAUST Catalysis Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Boon S Ooi
- Photonics Laboratory, Division of Computer, Electrical, and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Mohamed Eddaoudi
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Omar F Mohammed
- Advanced Membranes and Porous Materials Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
- KAUST Catalysis Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
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4
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Wang TY, Lai WC, Xie QJ, Yang SH, Chang SP, Kuo CH, Sheu JK. The influences of AlGaN barrier epitaxy in multiple quantum wells on the optoelectrical properties of AlGaN-based deep ultra-violet light-emitting diodes. RSC Adv 2023; 13:5437-5443. [PMID: 36793296 PMCID: PMC9923460 DOI: 10.1039/d2ra07368d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 02/06/2023] [Indexed: 02/16/2023] Open
Abstract
The growth conditions of the AlGaN barrier in AlGaN/AlGaN deep ultra-violet (DUV) multiple quantum wells (MQWs) have crucial influences on the light output power of DUV light-emitting diodes (LEDs). The reduction of the AlGaN barrier growth rate improved the qualities of AlGaN/AlGaN MQWs, such as surface roughness and defects. The light output power enhancement could reach 83% when the AlGaN barrier growth rate was reduced from 900 nm h-1 to 200 nm h-1. In addition to the light output power enhancement, lowering the AlGaN barrier growth rate altered the far-field emission patterns of the DUV LEDs and increased the degree of polarization in the DUV LEDs. The enhanced transverse electric polarized emission indicates that the strain in AlGaN/AlGaN MQWs was modified by lowering the AlGaN barrier growth rate.
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Affiliation(s)
- Tien-Yu Wang
- Department of Photonics, National Cheng Kung University Tainan 70101 Taiwan
| | - Wei-Chih Lai
- Department of Photonics, National Cheng Kung University Tainan 70101 Taiwan
- Advanced Optoelectronic Technology Center, Research Center for Energy Technology and Strategy, National Cheng Kung University Tainan 70101 Taiwan
| | - Qiao-Ju Xie
- Department of Photonics, National Cheng Kung University Tainan 70101 Taiwan
| | - Shun-Hao Yang
- Department of Photonics, National Cheng Kung University Tainan 70101 Taiwan
| | - Sheng-Po Chang
- Department of Photonics, National Cheng Kung University Tainan 70101 Taiwan
- Advanced Optoelectronic Technology Center, Research Center for Energy Technology and Strategy, National Cheng Kung University Tainan 70101 Taiwan
- Institute of Microelectronics and Department of Electrical Engineering, National Cheng Kung University Tainan 70101 Taiwan
| | - Cheng-Huang Kuo
- Institute of Lighting and Energy Photonics, College of Photonics, National Yang Ming Chiao Tung University Tainan 71150 Taiwan
| | - Jinn-Kong Sheu
- Department of Photonics, National Cheng Kung University Tainan 70101 Taiwan
- Advanced Optoelectronic Technology Center, Research Center for Energy Technology and Strategy, National Cheng Kung University Tainan 70101 Taiwan
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5
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Lv P, Li L, Yin Z, Wang C, Yang Y. Visible-to-ultraviolet-C upconverted photon for multifunction via Ca 2SiO 4:Pr 3. OPTICS LETTERS 2022; 47:4435-4438. [PMID: 36048672 DOI: 10.1364/ol.469090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
The ultraviolet C (UVC) photon plays a key role in a broad spectrum of fields. With the implementation of the Minamata Convention, searching for a new way to achieve UVC light is highly desired. Here we develop a material of Ca2SiO4:Pr3+ that can emit UVC light upon excitation of a 450-nm laser or even a very cheap 450-nm LED, a fact confirmed by using a solar blind camera to capture UVC emission from Ca2SiO4:Pr3+. In addition, smart anti-counterfeiting and inactivation of Bacillus subtilis applications using Ca2SiO4:Pr3+ are also confirmed.
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6
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Fully Relaxed, Crack-Free AlGaN with upto 50% Al Composition Grown on Porous GaN Pseudo-Substrate. CRYSTALS 2022. [DOI: 10.3390/cryst12070989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fully relaxed, crack free, smooth AlxGa1−xN layers with up to 50% Al composition were demonstrated on pseudo-substrates composed of dense arrays of 10 × 10 µm2 compliant porous GaN-on-porous-GaN tiles. The AlGaN layers were grown in steps for a total of 1.3 µm. The growth conditions necessary to demonstrate high quality films at higher Al compositions also suppressed any sidewall growth.
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7
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Li D, Liu S, Qian Z, Liu Q, Zhou K, Liu D, Sheng S, Sheng B, Liu F, Chen Z, Wang P, Wang T, Rong X, Tao R, Kang J, Chen F, Kang J, Yuan Y, Wang Q, Sun M, Ge W, Shen B, Tian P, Wang X. Deep-Ultraviolet Micro-LEDs Exhibiting High Output Power and High Modulation Bandwidth Simultaneously. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2109765. [PMID: 35297518 DOI: 10.1002/adma.202109765] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/20/2022] [Indexed: 06/14/2023]
Abstract
Deep-ultraviolet (DUV) solar-blind communication (SBC) shows distinct advantages of non-line-of-sight propagation and background noise negligibility over conventional visible-light communication. AlGaN-based DUV micro-light-emitting diodes (µ-LEDs) are an excellent candidate for a DUV-SBC light source due to their small size, low power consumption, and high modulation bandwidth. A long-haul DUV-SBC system requires the light source exhibiting high output power, high modulation bandwidth, and high rate, simultaneously. Such a device is rarely reported. A parallel-arrayed planar (PAP) approach is here proposed to satisfy those requirements. By reducing the dimensions of the active emission mesa to micrometer scale, DUV µ-LEDs with ultrahigh power density are created due to their homogeneous injection current and enhanced planar isotropic light emission. Interconnected PAP µ-LEDs with a diameter of 25 µm are produced. This device has an output power of 83.5 mW with a density of 405 W cm-2 at 230 mA, a wall-plug efficiency (WPE) of 4.7% at 155 mA, and a high -3 dB modulation bandwidth of 380 MHz. The remarkable high output power and efficiency make those devices a reliable platform to develop high-modulation-bandwidth wireless communication and to meet the requirements for bio-elimination.
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Affiliation(s)
- Duo Li
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Shangfeng Liu
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Zeyuan Qian
- School of Information Science and Technology, Fudan University, Shanghai, 200438, China
| | - Quanfeng Liu
- Dongguan Sino Crystal Semiconductor Co., Ltd., Dongguan, 523500, China
| | - Kang Zhou
- Dongguan Sino Crystal Semiconductor Co., Ltd., Dongguan, 523500, China
| | - Dandan Liu
- Dongguan Sino Crystal Semiconductor Co., Ltd., Dongguan, 523500, China
| | - Shanshan Sheng
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Bowen Sheng
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Fang Liu
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Zhaoying Chen
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Ping Wang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Tao Wang
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
| | - Xin Rong
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Renchun Tao
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Jianbin Kang
- Microsystem and Terahertz Research Center, China Academy of Engineering Physics, Chengdu, 610200, China
| | - Feiliang Chen
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 611731, China
| | - Junjie Kang
- Songshan Lake Materials Laboratory, Dongguan, 523808, China
| | - Ye Yuan
- Songshan Lake Materials Laboratory, Dongguan, 523808, China
| | - Qi Wang
- Dongguan Institute of Opto-Electronics Peking University, Dongguan, 523808, China
| | - Ming Sun
- Dongguan Sino Crystal Semiconductor Co., Ltd., Dongguan, 523500, China
| | - Weikun Ge
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Bo Shen
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
- Collaborative Innovation Center of Quantum Matter, School of Physics, Peking University, Beijing, 100871, China
| | - Pengfei Tian
- School of Information Science and Technology, Fudan University, Shanghai, 200438, China
| | - Xinqiang Wang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, 100871, China
- Dongguan Institute of Opto-Electronics Peking University, Dongguan, 523808, China
- Collaborative Innovation Center of Quantum Matter, School of Physics, Peking University, Beijing, 100871, China
- Peking University Yangtze Delta Institute of Optoelectronics, Nantong, Jiangsu, 226010, China
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Sait M, Trichili A, Alkhazragi O, Alshaibaini S, Ng TK, Alouini MS, Ooi BS. Dual-wavelength luminescent fibers receiver for wide field-of-view, Gb/s underwater optical wireless communication. OPTICS EXPRESS 2021; 29:38014-38026. [PMID: 34808862 DOI: 10.1364/oe.443255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/20/2021] [Indexed: 06/13/2023]
Abstract
Extending the field-of-view (FoV) of underwater wireless optical communication (UWOC) receivers can significantly ease the need for active positioning and tracking mechanisms. Two bundle of scintillating fibers emitting at 430- and 488-nm were used to detect two independent signals from ultraviolet and visible laser sources. A zero-forcing approach to minimize inter-channel crosstalk was further implemented. A net aggregated UWOC data rate of 1 Gb/s was achieved using two wavelengths and a non-return-to-zero on-off keying scheme.
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9
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Yu H, Jia H, Liu Z, Memon MH, Tian M, Fang S, Wang D, Zhang H, Liu J, Xu L, Yang T, Wei L, Liao Z, Sun H. Development of highly efficient ultraviolet LEDs on hybrid patterned sapphire substrates. OPTICS LETTERS 2021; 46:5356-5359. [PMID: 34724474 DOI: 10.1364/ol.441300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
A hybrid patterned sapphire substrate (HPSS) aiming to achieve high-quality Al(Ga)N epilayers for the development of GaN-based ultraviolet light-emitting diodes (UV LEDs) has been prepared. The high-resolution X-ray diffraction measurements reveal that the Al(Ga)N epilayers grown on a HPSS and conventional patterned sapphire substrate (CPSS) have similar structural quality. More importantly, benefiting from the larger refractive index contrast between the patterned silica array and sapphire, the photons can escape from the hybrid substrate with an improved transmittance in the UV band. As a result, in comparison with the UV LEDs grown on the CPSS, the LEDs grown on the HPSS exhibit a significantly enhanced light output power by 14.5% and more than 22.9% higher peak external quantum efficiency, owing to the boost of the light extraction efficiency from the adoption of the HPSS which can be used as a promising substrate to realize high-efficiency and high-power UV LEDs of the future.
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Tian M, Yu H, Memon MH, Xing Z, Huang C, Jia H, Zhang H, Wang D, Fang S, Sun H. Enhanced light extraction of the deep-ultraviolet micro-LED via rational design of chip sidewall. OPTICS LETTERS 2021; 46:4809-4812. [PMID: 34598205 DOI: 10.1364/ol.441285] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
In this Letter, we perform a comprehensive investigation on the optical characterization of micro-sized deep-ultraviolet (DUV) LEDs (micro-LEDs) emitting below 280 nm, highlighting the light extraction behavior in relation to the design of chip sidewall angle. We found that the micro-LEDs with a smaller inclined chip sidewall angle (∼33∘) have improved external quantum efficiency (EQE) performance 19% more than that of the micro-LEDs with a larger angle (∼75∘). Most importantly, the EQE improvement by adopting an inclined sidewall can be more outstanding as the diameter of the LED chip reduces from 40 to 20 μm. The enhanced EQE of the micro-LEDs with smaller inclined chip sidewall angles can be attributed to the stronger reflection of the inclined sidewall, leading to enhanced light extraction efficiency (LEE). In the end, the numerical optical modeling further reveals and verifies the impact of the sidewall angles on the LEE of the micro-LEDs, corroborating our experiment results. This Letter provides a fundamental understanding of the light extraction behavior with optimized chip geometry to design and fabricate highly efficient micro-LEDs in a DUV spectrum of the future.
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Yan S, Liang Y, Chen Y, Liu J, Chen D, Pan Z. Ultraviolet-C persistent luminescence from the Lu 2SiO 5:Pr 3+ persistent phosphor for solar-blind optical tagging. Dalton Trans 2021; 50:8457-8466. [PMID: 34047327 DOI: 10.1039/d1dt00791b] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Visible and infrared persistent phosphors have gained considerable attention in recent years and are being widely used as glow-in-the-dark materials in dark environments. In contrast, the progress in persistent phosphors emitting at the other end of the spectrum, i.e., the shorter-wavelength ultraviolet-C (UVC; 200-280 nm), is rather slow. Here we report the design and synthesis of a well-performing Pr3+-doped UVC emissive persistent phosphor, Lu2SiO5:Pr3+, which exhibits intense UVC persistent luminescence peaking at 270 nm and a long persistence time of more than 12 h after excitation with a 254 nm UV lamp. Besides, the UVC persistent luminescence of a UV pre-irradiated sample can be repeatedly revived after repeated short-illumination with low-energy white light via a process called photostimulated persistent luminescence. Owing to the distinct spectral features of UVC light and the self-sustained luminescence properties, the UVC persistent luminescence of the Lu2SiO5:Pr3+ persistent phosphor can be clearly monitored and imaged using a corona camera in bright environments including direct sunlight and indoor light. The Lu2SiO5:Pr3+ persistent phosphor is expected to find promising applications in the covert optical tagging field.
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Affiliation(s)
- Shao Yan
- Key Laboratory for Liquid-Solid Structure Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, P. R. China.
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12
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Zhu S, Qiu P, Qian Z, Shan X, Wang Z, Jiang K, Sun X, Cui X, Zhang G, Li D, Tian P. 2 Gbps free-space ultraviolet-C communication based on a high-bandwidth micro-LED achieved with pre-equalization. OPTICS LETTERS 2021; 46:2147-2150. [PMID: 33929440 DOI: 10.1364/ol.423311] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 04/03/2021] [Indexed: 06/12/2023]
Abstract
In this Letter, we experimentally achieve high-speed ultraviolet-C (UVC) communication based on a 276.8 nm UVC micro-LED. A record ${-}{{3}}\;{\rm{dB}}$ optical bandwidth of 452.53 MHz and light output power of 0.854 mW at a current density of ${{400}}\;{\rm{A/c}}{{\rm{m}}^2}$ are obtained with a chip size of 100 µm. A UVC link over 0.5 m with a data rate of 2 Gbps is achieved using 16-ary quadrature amplitude modulation orthogonal frequency division multiplexing and pre-equalization, and an extended distance over 3 m with a data rate of 0.82 Gbps is also presented. The demonstrated high-speed performance shows that micro-LEDs have great potential in the field of UVC communication.
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