Pub Date : 2024-06-07DOI: 10.1007/s12200-024-00121-7
Junjun Xue, Jiaming Tong, Zhujun Gao, Zhouyu Chen, Haoyu Fang, Saisai Wang, Ting Zhi, Jin Wang
An ultraviolet-infrared (UV-IR) dual-wavelength photodetector (PD) based on a monolayer (ML) graphene/GaN heterostructure has been successfully fabricated in this work. The ML graphene was synthesized by chemical vapor deposition (CVD) and subsequently transferred onto GaN substrate using polymethylmethacrylate (PMMA). The morphological and optical properties of the as-prepared graphene and GaN were presented. The fabricated PD based on the graphene/GaN heterostructure exhibited excellent rectify behavior by measuring the current-voltage (I-V) characteristics under dark conditions, and the spectral response demonstrated that the device revealed an UV-IR dual-wavelength photoresponse. In addition, the energy band structure and absorption properties of the ML graphene/GaN heterostructure were theoretically investigated based on density functional theory (DFT) to explore the underlying physical mechanism of the two-dimensional (2D)/three-dimensional (3D) hybrid heterostructure PD device. This work paves the way for the development of innovative GaN-based dual-wavelength optoelectronic devices, offering a potential strategy for future applications in the field of advanced photodetection technology.
在这项工作中,我们成功地制造出了基于单层(ML)石墨烯/氮化镓异质结构的紫外-红外(UV-IR)双波长光电探测器(PD)。单层石墨烯是通过化学气相沉积(CVD)合成的,随后使用聚甲基丙烯酸甲酯(PMMA)转移到氮化镓衬底上。研究介绍了制备的石墨烯和 GaN 的形态和光学特性。通过测量黑暗条件下的电流-电压(I-V)特性,基于石墨烯/氮化镓异质结构制备的 PD 表现出优异的整流性能,光谱响应表明该器件具有紫外-红外双波长光响应。此外,还基于密度泛函理论(DFT)对 ML 石墨烯/氮化镓异质结构的能带结构和吸收特性进行了理论研究,以探索二维(2D)/三维(3D)混合异质结构 PD 器件的基本物理机制。这项工作为开发基于氮化镓的创新型双波长光电器件铺平了道路,为未来在先进光探测技术领域的应用提供了一种潜在的策略。
{"title":"Monolayer graphene/GaN heterostructure photodetector with UV-IR dual-wavelength photoresponses.","authors":"Junjun Xue, Jiaming Tong, Zhujun Gao, Zhouyu Chen, Haoyu Fang, Saisai Wang, Ting Zhi, Jin Wang","doi":"10.1007/s12200-024-00121-7","DOIUrl":"10.1007/s12200-024-00121-7","url":null,"abstract":"<p><p>An ultraviolet-infrared (UV-IR) dual-wavelength photodetector (PD) based on a monolayer (ML) graphene/GaN heterostructure has been successfully fabricated in this work. The ML graphene was synthesized by chemical vapor deposition (CVD) and subsequently transferred onto GaN substrate using polymethylmethacrylate (PMMA). The morphological and optical properties of the as-prepared graphene and GaN were presented. The fabricated PD based on the graphene/GaN heterostructure exhibited excellent rectify behavior by measuring the current-voltage (I-V) characteristics under dark conditions, and the spectral response demonstrated that the device revealed an UV-IR dual-wavelength photoresponse. In addition, the energy band structure and absorption properties of the ML graphene/GaN heterostructure were theoretically investigated based on density functional theory (DFT) to explore the underlying physical mechanism of the two-dimensional (2D)/three-dimensional (3D) hybrid heterostructure PD device. This work paves the way for the development of innovative GaN-based dual-wavelength optoelectronic devices, offering a potential strategy for future applications in the field of advanced photodetection technology.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"17"},"PeriodicalIF":5.4,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11161448/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141283486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In current documented studies, it has been observed that wavelength converters utilizing AlGaAsOI waveguides exhibit suboptimal on-chip wavelength conversion efficiency from the C-band to the 2 μm band, generally falling below -20.0 dB. To address this issue, we present a novel wavelength conversion device assisted by a waveguide amplifier, incorporating both AlGaAs wavelength converter and erbium-ytterbium co-doped waveguide amplifier, thereby achieving a notable conversion efficiency exceeding 0 dB. The noteworthy enhancement in efficiency can be attributed to the specific dispersion design of the AlGaAs wavelength converter, which enables an upsurge in conversion efficiency to -15.54 dB under 100 mW of pump power. Furthermore, the integration of an erbium-ytterbium co-doped waveguide amplifier facilitates a loss compensation of over 15 dB. Avoiding the use of external optical amplifiers, this device enables efficient and high-bandwidth wavelength conversion, showing promising applications in various fields, such as optical communication, sensing, imaging, and beyond.
{"title":"Design of an on-chip wavelength conversion device assisted by an erbium-ytterbium co-doped waveguide amplifier.","authors":"Chen Zhou, Xiwen He, Mingyue Xiao, Deyue Ma, Weibiao Chen, Zhiping Zhou","doi":"10.1007/s12200-024-00118-2","DOIUrl":"10.1007/s12200-024-00118-2","url":null,"abstract":"<p><p>In current documented studies, it has been observed that wavelength converters utilizing AlGaAsOI waveguides exhibit suboptimal on-chip wavelength conversion efficiency from the C-band to the 2 μm band, generally falling below -20.0 dB. To address this issue, we present a novel wavelength conversion device assisted by a waveguide amplifier, incorporating both AlGaAs wavelength converter and erbium-ytterbium co-doped waveguide amplifier, thereby achieving a notable conversion efficiency exceeding 0 dB. The noteworthy enhancement in efficiency can be attributed to the specific dispersion design of the AlGaAs wavelength converter, which enables an upsurge in conversion efficiency to -15.54 dB under 100 mW of pump power. Furthermore, the integration of an erbium-ytterbium co-doped waveguide amplifier facilitates a loss compensation of over 15 dB. Avoiding the use of external optical amplifiers, this device enables efficient and high-bandwidth wavelength conversion, showing promising applications in various fields, such as optical communication, sensing, imaging, and beyond.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"16"},"PeriodicalIF":5.4,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11150233/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141237427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chiral inorganic semiconductors with high dissymmetric factor are highly desirable, but it is generally difficult to induce chiral structure in inorganic semiconductors because of their structure rigidity and symmetry. In this study, we introduced chiral ZnO film as hard template to transfer chirality to CsPbBr3 film and PbS quantum dots (QDs) for circularly polarized light (CPL) emission and detection, respectively. The prepared CsPbBr3/ZnO thin film exhibited CPL emission at 520 nm and the PbS QDs/ZnO film realized CPL detection at 780 nm, featuring high dissymmetric factor up to around 0.4. The electron transition based mechanism is responsible for chirality transfer.
{"title":"Circularly polarized light emission and detection by chiral inorganic semiconductors.","authors":"Zha Li, Wancai Li, Dehui Li, Wei Tang, Huageng Liang, Huaibing Song, Chao Chen, Liang Gao, Jiang Tang","doi":"10.1007/s12200-024-00120-8","DOIUrl":"10.1007/s12200-024-00120-8","url":null,"abstract":"<p><p>Chiral inorganic semiconductors with high dissymmetric factor are highly desirable, but it is generally difficult to induce chiral structure in inorganic semiconductors because of their structure rigidity and symmetry. In this study, we introduced chiral ZnO film as hard template to transfer chirality to CsPbBr<sub>3</sub> film and PbS quantum dots (QDs) for circularly polarized light (CPL) emission and detection, respectively. The prepared CsPbBr<sub>3</sub>/ZnO thin film exhibited CPL emission at 520 nm and the PbS QDs/ZnO film realized CPL detection at 780 nm, featuring high dissymmetric factor up to around 0.4. The electron transition based mechanism is responsible for chirality transfer.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"15"},"PeriodicalIF":5.4,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11143083/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141179502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-28DOI: 10.1007/s12200-024-00117-3
Bo Ren, Hongxiang Chang, Can Li, Tao Wang, Kaikai Jin, Jiayi Zhang, Kun Guo, Rongtao Su, Jinyong Leng, Pu Zhou
In this paper, we report a coherent beam combining (CBC) system that involves two thulium-doped all-polarization maintaining (PM) fiber chirped pulse amplifiers. Through phase-locking the two channels via a fiber stretcher by using the stochastic parallel gradient descent (SPGD) algorithm, a maximum average power of 265 W is obtained, with a CBC efficiency of 81% and a residual phase error of λ/17. After de-chirping by a pair of diffraction gratings, the duration of the combined laser pulse is compressed to 690 fs. Taking into account the compression efficiency of 90% and the main peak energy proportion of 91%, the corresponding peak power is calculated to be 4 MW. The laser noise characteristics before and after CBC are examined, and the results indicate that the CBC would degrade the low frequency relative intensity noise (RIN), of which the integration is 1.74% in [100 Hz, 2 MHz] at the maximum combined output power. In addition, the effects of the nonlinear spectrum broadening during chirped pulse amplification on the CBC efficiency are also investigated, showing that a higher extent of pulse stretching is effective in alleviating the spectrum broadening and realizing a higher output power with decent combining efficiency.
{"title":"Coherent beam combining of two all-PM thulium-doped fiber chirped pulse amplifiers.","authors":"Bo Ren, Hongxiang Chang, Can Li, Tao Wang, Kaikai Jin, Jiayi Zhang, Kun Guo, Rongtao Su, Jinyong Leng, Pu Zhou","doi":"10.1007/s12200-024-00117-3","DOIUrl":"https://doi.org/10.1007/s12200-024-00117-3","url":null,"abstract":"<p><p>In this paper, we report a coherent beam combining (CBC) system that involves two thulium-doped all-polarization maintaining (PM) fiber chirped pulse amplifiers. Through phase-locking the two channels via a fiber stretcher by using the stochastic parallel gradient descent (SPGD) algorithm, a maximum average power of 265 W is obtained, with a CBC efficiency of 81% and a residual phase error of λ/17. After de-chirping by a pair of diffraction gratings, the duration of the combined laser pulse is compressed to 690 fs. Taking into account the compression efficiency of 90% and the main peak energy proportion of 91%, the corresponding peak power is calculated to be 4 MW. The laser noise characteristics before and after CBC are examined, and the results indicate that the CBC would degrade the low frequency relative intensity noise (RIN), of which the integration is 1.74% in [100 Hz, 2 MHz] at the maximum combined output power. In addition, the effects of the nonlinear spectrum broadening during chirped pulse amplification on the CBC efficiency are also investigated, showing that a higher extent of pulse stretching is effective in alleviating the spectrum broadening and realizing a higher output power with decent combining efficiency.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"14"},"PeriodicalIF":5.4,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141157602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-27DOI: 10.1007/s12200-024-00116-4
Zhixiang Huang, Weipeng Wu, Eric Herrmann, Ke Ma, Zizwe A Chase, Thomas A Searles, M Benjamin Jungfleisch, Xi Wang
The non-ionizing and penetrative characteristics of terahertz (THz) radiation have recently led to its adoption across a variety of applications. To effectively utilize THz radiation, modulators with precise control are imperative. While most recent THz modulators manipulate the amplitude, frequency, or phase of incident THz radiation, considerably less progress has been made toward THz polarization modulation. Conventional methods for polarization control suffer from high driving voltages, restricted modulation depth, and narrow band capabilities, which hinder device performance and broader applications. Consequently, an ideal THz modulator that offers high modulation depth along with ease of processing and operation is required. In this paper, we propose and realize a THz metamaterial comprised of microelectromechanical systems (MEMS) actuated by the phase-transition material vanadium dioxide (VO2). Simulation and experimental results of the three-dimensional metamaterials show that by leveraging the unique phase-transition attributes of VO2, our THz polarization modulator offers notable advancements over existing designs, including broad operation spectrum, high modulation depth, ease of fabrication, ease of operation condition, and continuous modulation capabilities. These enhanced features make the system a viable candidate for a range of THz applications, including telecommunications, imaging, and radar systems.
{"title":"MEMS-actuated terahertz metamaterials driven by phase-transition materials.","authors":"Zhixiang Huang, Weipeng Wu, Eric Herrmann, Ke Ma, Zizwe A Chase, Thomas A Searles, M Benjamin Jungfleisch, Xi Wang","doi":"10.1007/s12200-024-00116-4","DOIUrl":"10.1007/s12200-024-00116-4","url":null,"abstract":"<p><p>The non-ionizing and penetrative characteristics of terahertz (THz) radiation have recently led to its adoption across a variety of applications. To effectively utilize THz radiation, modulators with precise control are imperative. While most recent THz modulators manipulate the amplitude, frequency, or phase of incident THz radiation, considerably less progress has been made toward THz polarization modulation. Conventional methods for polarization control suffer from high driving voltages, restricted modulation depth, and narrow band capabilities, which hinder device performance and broader applications. Consequently, an ideal THz modulator that offers high modulation depth along with ease of processing and operation is required. In this paper, we propose and realize a THz metamaterial comprised of microelectromechanical systems (MEMS) actuated by the phase-transition material vanadium dioxide (VO<sub>2</sub>). Simulation and experimental results of the three-dimensional metamaterials show that by leveraging the unique phase-transition attributes of VO<sub>2</sub>, our THz polarization modulator offers notable advancements over existing designs, including broad operation spectrum, high modulation depth, ease of fabrication, ease of operation condition, and continuous modulation capabilities. These enhanced features make the system a viable candidate for a range of THz applications, including telecommunications, imaging, and radar systems.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"13"},"PeriodicalIF":5.4,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11128424/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141155147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.1007/s12200-024-00115-5
Yupei Liang, Mingyu Liu, Fan Tang, Yanhong Guo, Hao Zhang, Shihan Liu, Yanping Yang, Guangming Zhao, Teng Tan, Baicheng Yao
Since their inception, frequency combs generated in microresonators, known as microcombs, have sparked significant scientific interests. Among the various applications leveraging microcombs, soliton microcombs are often preferred due to their inherent mode-locking capability. However, this choice introduces additional system complexity because an initialization process is required. Meanwhile, despite the theoretical understanding of the dynamics of other comb states, their practical potential, particularly in applications like sensing where simplicity is valued, remains largely untapped. Here, we demonstrate controllable generation of sub-combs that bypasses the need for accessing bistable regime. And in a graphene-sensitized microresonator, the sub-comb heterodynes produce stable, accurate microwave signals for high-precision gas detection. By exploring the formation dynamics of sub-combs, we achieved 2 MHz harmonic comb-to-comb beat notes with a signal-to-noise ratio (SNR) greater than 50 dB and phase noise as low as - 82 dBc/Hz at 1 MHz offset. The graphene sensitization on the intracavity probes results in exceptional frequency responsiveness to the adsorption of gas molecules on the graphene of microcavity surface, enabling detect limits down to the parts per billion (ppb) level. This synergy between graphene and sub-comb formation dynamics in a microcavity structure showcases the feasibility of utilizing microcombs in an incoherent state prior to soliton locking. It may mark a significant step toward the development of easy-to-operate, systemically simple, compact, and high-performance photonic sensors.
{"title":"Harnessing sub-comb dynamics in a graphene-sensitized microresonator for gas detection.","authors":"Yupei Liang, Mingyu Liu, Fan Tang, Yanhong Guo, Hao Zhang, Shihan Liu, Yanping Yang, Guangming Zhao, Teng Tan, Baicheng Yao","doi":"10.1007/s12200-024-00115-5","DOIUrl":"https://doi.org/10.1007/s12200-024-00115-5","url":null,"abstract":"<p><p>Since their inception, frequency combs generated in microresonators, known as microcombs, have sparked significant scientific interests. Among the various applications leveraging microcombs, soliton microcombs are often preferred due to their inherent mode-locking capability. However, this choice introduces additional system complexity because an initialization process is required. Meanwhile, despite the theoretical understanding of the dynamics of other comb states, their practical potential, particularly in applications like sensing where simplicity is valued, remains largely untapped. Here, we demonstrate controllable generation of sub-combs that bypasses the need for accessing bistable regime. And in a graphene-sensitized microresonator, the sub-comb heterodynes produce stable, accurate microwave signals for high-precision gas detection. By exploring the formation dynamics of sub-combs, we achieved 2 MHz harmonic comb-to-comb beat notes with a signal-to-noise ratio (SNR) greater than 50 dB and phase noise as low as - 82 dBc/Hz at 1 MHz offset. The graphene sensitization on the intracavity probes results in exceptional frequency responsiveness to the adsorption of gas molecules on the graphene of microcavity surface, enabling detect limits down to the parts per billion (ppb) level. This synergy between graphene and sub-comb formation dynamics in a microcavity structure showcases the feasibility of utilizing microcombs in an incoherent state prior to soliton locking. It may mark a significant step toward the development of easy-to-operate, systemically simple, compact, and high-performance photonic sensors.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"12"},"PeriodicalIF":5.4,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11061063/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140858285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The topological photonics plays an important role in the fields of fundamental physics and photonic devices. The traditional method of designing topological system is based on the momentum space, which is not a direct and convenient way to grasp the topological properties, especially for the perturbative structures or coupled systems. Here, we propose an interdisciplinary approach to study the topological systems in real space through combining the information entropy and topological photonics. As a proof of concept, the Kagome model has been analyzed with information entropy. We reveal that the bandgap closing does not correspond to the topological edge state disappearing. This method can be used to identify the topological phase conveniently and directly, even the systems with perturbations or couplings. As a promotional validation, Su-Schrieffer-Heeger model and the valley-Hall photonic crystal have also been studied based on the information entropy method. This work provides a method to study topological photonic phase based on information theory, and brings inspiration to analyze the physical properties by taking advantage of interdisciplinarity.
{"title":"Information-entropy enabled identifying topological photonic phase in real space.","authors":"Rui Ma, Qiuchen Yan, Yihao Luo, Yandong Li, Xingyuan Wang, Cuicui Lu, Xiaoyong Hu, Qihuang Gong","doi":"10.1007/s12200-024-00113-7","DOIUrl":"https://doi.org/10.1007/s12200-024-00113-7","url":null,"abstract":"<p><p>The topological photonics plays an important role in the fields of fundamental physics and photonic devices. The traditional method of designing topological system is based on the momentum space, which is not a direct and convenient way to grasp the topological properties, especially for the perturbative structures or coupled systems. Here, we propose an interdisciplinary approach to study the topological systems in real space through combining the information entropy and topological photonics. As a proof of concept, the Kagome model has been analyzed with information entropy. We reveal that the bandgap closing does not correspond to the topological edge state disappearing. This method can be used to identify the topological phase conveniently and directly, even the systems with perturbations or couplings. As a promotional validation, Su-Schrieffer-Heeger model and the valley-Hall photonic crystal have also been studied based on the information entropy method. This work provides a method to study topological photonic phase based on information theory, and brings inspiration to analyze the physical properties by taking advantage of interdisciplinarity.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"11"},"PeriodicalIF":5.4,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11056353/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140857809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-28DOI: 10.1007/s12200-024-00111-9
Jian Yin, David Hwang, Hossein Zamani Siboni, Ehsanollah Fathi, Reza Chaji, Dayan Ban
InGaN/GaN micro-light-emitting diodes (micro-LEDs) with a metal-insulator-semiconductor (MIS) structure on the sidewall are proposed to improve efficiency. In this MIS structure, a sidewall electrode is deposited on the insulating layer-coated sidewall of the device mesa between a cathode on the bottom and an anode on the top. Electroluminescence (EL) measurements of fabricated devices with a mesa diameter of 10 μm show that the application of negative biases on the sidewall electrode can increase the device external quantum efficiency (EQE). In contrast, the application of positive biases can decrease the EQE. The band structure analysis reveals that the EQE is impacted because the application of sidewall electric fields manipulates the local surface electron density along the mesa sidewall and thus controls surface Shockley-Read-Hall (SRH) recombination. Two suggested strategies, reducing insulator layer thickness and exploring alternative materials, can be implemented to further improve the EQE of MIS micro-LEDs in future fabrication.
为了提高效率,提出了在侧壁上采用金属-绝缘体-半导体(MIS)结构的 InGaN/GaN 微型发光二极管(micro-LED)。在这种金属-绝缘体-半导体(MIS)结构中,侧壁电极沉积在底部阴极和顶部阳极之间的器件介子的绝缘层涂层侧壁上。对介子直径为 10 μm 的器件进行的电致发光(EL)测量表明,在侧壁电极上施加负偏压可提高器件的外部量子效率(EQE)。相反,施加正偏压则会降低 EQE。带状结构分析表明,影响 EQE 的原因是侧壁电场的应用操纵了沿介子侧壁的局部表面电子密度,从而控制了表面肖克利-雷德-霍尔(SRH)重组。建议采取减少绝缘层厚度和探索替代材料这两种策略,以便在未来的制造过程中进一步提高 MIS 微型 LED 的 EQE。
{"title":"Efficiency improvement by using metal-insulator-semiconductor structure in InGaN/GaN micro-light-emitting diodes.","authors":"Jian Yin, David Hwang, Hossein Zamani Siboni, Ehsanollah Fathi, Reza Chaji, Dayan Ban","doi":"10.1007/s12200-024-00111-9","DOIUrl":"10.1007/s12200-024-00111-9","url":null,"abstract":"<p><p>InGaN/GaN micro-light-emitting diodes (micro-LEDs) with a metal-insulator-semiconductor (MIS) structure on the sidewall are proposed to improve efficiency. In this MIS structure, a sidewall electrode is deposited on the insulating layer-coated sidewall of the device mesa between a cathode on the bottom and an anode on the top. Electroluminescence (EL) measurements of fabricated devices with a mesa diameter of 10 μm show that the application of negative biases on the sidewall electrode can increase the device external quantum efficiency (EQE). In contrast, the application of positive biases can decrease the EQE. The band structure analysis reveals that the EQE is impacted because the application of sidewall electric fields manipulates the local surface electron density along the mesa sidewall and thus controls surface Shockley-Read-Hall (SRH) recombination. Two suggested strategies, reducing insulator layer thickness and exploring alternative materials, can be implemented to further improve the EQE of MIS micro-LEDs in future fabrication.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"8"},"PeriodicalIF":5.4,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10973746/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140318119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-19DOI: 10.1007/s12200-024-00110-w
Zhuochen Du, Jinze Gao, Qiuchen Yan, Cuicui Lu, Xiaoyong Hu, Qihuang Gong
Modulation of topological phase transition has been pursued by researchers in both condensed matter and optics research fields, and has been realized in Euclidean systems, such as topological photonic crystals, topological metamaterials, and coupled resonator arrays. However, the spin-controlled topological phase transition in non-Euclidean space has not yet been explored. Here, we propose a non-Euclidean configuration based on Möbius rings, and we demonstrate the spin-controlled transition between the topological edge state and the bulk state. The Möbius ring, which is designed to have an 8π period, has a square cross section at the twist beginning and the length/width evolves adiabatically along the loop, accompanied by conversion from transverse electric to transverse magnetic modes resulting from the spin-locked effect. The 8π period Möbius rings are used to construct Su-Schrieffer-Heeger configuration, and the configuration can support the topological edge states excited by circularly polarized light, and meanwhile a transition from the topological edge state to the bulk state can be realized by controlling circular polarization. In addition, the spin-controlled topological phase transition in non-Euclidean space is feasible for both Hermitian and non-Hermitian cases in 2D systems. This work provides a new degree of polarization to control topological photonic states based on the spin of Möbius rings and opens a way to tune the topological phase in non-Euclidean space.
{"title":"Spin-controlled topological phase transition in non-Euclidean space.","authors":"Zhuochen Du, Jinze Gao, Qiuchen Yan, Cuicui Lu, Xiaoyong Hu, Qihuang Gong","doi":"10.1007/s12200-024-00110-w","DOIUrl":"10.1007/s12200-024-00110-w","url":null,"abstract":"<p><p>Modulation of topological phase transition has been pursued by researchers in both condensed matter and optics research fields, and has been realized in Euclidean systems, such as topological photonic crystals, topological metamaterials, and coupled resonator arrays. However, the spin-controlled topological phase transition in non-Euclidean space has not yet been explored. Here, we propose a non-Euclidean configuration based on Möbius rings, and we demonstrate the spin-controlled transition between the topological edge state and the bulk state. The Möbius ring, which is designed to have an 8π period, has a square cross section at the twist beginning and the length/width evolves adiabatically along the loop, accompanied by conversion from transverse electric to transverse magnetic modes resulting from the spin-locked effect. The 8π period Möbius rings are used to construct Su-Schrieffer-Heeger configuration, and the configuration can support the topological edge states excited by circularly polarized light, and meanwhile a transition from the topological edge state to the bulk state can be realized by controlling circular polarization. In addition, the spin-controlled topological phase transition in non-Euclidean space is feasible for both Hermitian and non-Hermitian cases in 2D systems. This work provides a new degree of polarization to control topological photonic states based on the spin of Möbius rings and opens a way to tune the topological phase in non-Euclidean space.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"7"},"PeriodicalIF":5.4,"publicationDate":"2024-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10951149/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140174236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-20DOI: 10.1007/s12200-024-00109-3
Yitong Lin, Yu Zhong, Yangpeng Lin, Jiawei Lin, Lei Pang, Zhilong Zhang, Yi Zhao, Xiao-Ying Huang, Ke-Zhao Du
With the rapid development of white LEDs, the research of new and efficient white light emitting materials has attracted increasing attention. Zero dimensional (0D) organic-inorganic hybrid metal halide perovskites with superior luminescent property are promising candidates for LED application, due to their abundant and tailorable structure. Herein, [(CH3)3S]2SnCl6·H2O is synthesized as a host for dopant ions Bi3+ and Sb3+. The Sb3+ doped, or Bi3+/Sb3+ co-doped, [(CH3)3S]2SnCl6·H2O has a tunable optical emission spectrum by means of varying dopant ratio and excitation wavelength. As a result, we can achieve single-phase materials suitable for emission ranging from cold white light to warm white light. The intrinsic mechanism is examined in this work, to clarify the dopant effect on the optical properties. The high stability of title crystalline material, against water, oxygen and heat, makes it promising for further application.
随着白光 LED 的快速发展,新型高效白光发光材料的研究日益受到关注。具有优异发光性能的零维(0D)有机-无机杂化金属卤化物过氧化物因其丰富且可定制的结构而成为 LED 应用的理想候选材料。本文合成了[(CH3)3S]2SnCl6-H2O,作为掺杂离子 Bi3+ 和 Sb3+ 的宿主。通过改变掺杂比例和激发波长,掺杂 Sb3+ 或 Bi3+/Sb3+ 共掺杂的 [(CH3)3S]2SnCl6-H2O 具有可调的光学发射光谱。因此,我们可以获得适用于从冷白光到暖白光发射的单相材料。这项工作对其内在机理进行了研究,以阐明掺杂剂对光学特性的影响。标题晶体材料对水、氧和热的高稳定性使其具有进一步应用的前景。
{"title":"White light emission in 0D halide perovskite [(CH<sub>3</sub>)<sub>3</sub>S]<sub>2</sub>SnCl<sub>6</sub>·H<sub>2</sub>O crystals through variation of doping ns<sup>2</sup> ions.","authors":"Yitong Lin, Yu Zhong, Yangpeng Lin, Jiawei Lin, Lei Pang, Zhilong Zhang, Yi Zhao, Xiao-Ying Huang, Ke-Zhao Du","doi":"10.1007/s12200-024-00109-3","DOIUrl":"10.1007/s12200-024-00109-3","url":null,"abstract":"<p><p>With the rapid development of white LEDs, the research of new and efficient white light emitting materials has attracted increasing attention. Zero dimensional (0D) organic-inorganic hybrid metal halide perovskites with superior luminescent property are promising candidates for LED application, due to their abundant and tailorable structure. Herein, [(CH<sub>3</sub>)<sub>3</sub>S]<sub>2</sub>SnCl<sub>6</sub>·H<sub>2</sub>O is synthesized as a host for dopant ions Bi<sup>3+</sup> and Sb<sup>3+</sup>. The Sb<sup>3+</sup> doped, or Bi<sup>3+</sup>/Sb<sup>3+</sup> co-doped, [(CH<sub>3</sub>)<sub>3</sub>S]<sub>2</sub>SnCl<sub>6</sub>·H<sub>2</sub>O has a tunable optical emission spectrum by means of varying dopant ratio and excitation wavelength. As a result, we can achieve single-phase materials suitable for emission ranging from cold white light to warm white light. The intrinsic mechanism is examined in this work, to clarify the dopant effect on the optical properties. The high stability of title crystalline material, against water, oxygen and heat, makes it promising for further application.</p>","PeriodicalId":12685,"journal":{"name":"Frontiers of Optoelectronics","volume":"17 1","pages":"6"},"PeriodicalIF":4.1,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10876505/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139905530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}