Journals >Semiconductor Optoelectronics
Contents
2024
Volume: 45 Issue 3
27 Article(s)
Export citation format
Advancements in Generating and Tuning Fano Resonances Using Silicon-Based Microring Resonators
XU Qiang, SUN Shibo, LIXinyu, KONG Mei, and XU Yameng
Fano resonances ,known fortheirasymmetriclineshapes ,show greatpromisein optical communication ,modulation ,and sensing. This study explores differentline shapes using microring resonatorsand highlightsthe distinctadvantagesofFano resonance. Firstly ,wereview research progresson generatingFano resonancewith silicon-basFano resonances ,known fortheirasymmetriclineshapes ,show greatpromisein optical communication ,modulation ,and sensing. This study explores differentline shapes using microring resonatorsand highlightsthe distinctadvantagesofFano resonance. Firstly ,wereview research progresson generatingFano resonancewith silicon-based microring resonators ,focusing on resonator structures. Secondly ,we discuss advancements in tuning Fano resonance using the thermo-optic effect. Finally ,we explore future developments and applications ofFano resonance with silicon-based microring resonators..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 341 (2024)
Temperature and Refractive Index Sensor Based on Multimode Fiber Cascaded Fabry-Perot Cavities
YAO Guozhen, ZONG Zitian, WU Yuzhang, LIBingfeng, YAN Bingxin, and SHANG Qiufeng
A temperature and refractive index dual-parameter sensor composed of a cascade of a single-mode fiberBragggrating and a multi-mode Fabry-Perotcavityisproposed. The end of the multi-mode optical fiber is etched with hydrofluoric acid ,and then the depression formed after etching is filled with ultravioletglue to form a A temperature and refractive index dual-parameter sensor composed of a cascade of a single-mode fiberBragggrating and a multi-mode Fabry-Perotcavityisproposed. The end of the multi-mode optical fiber is etched with hydrofluoric acid ,and then the depression formed after etching is filled with ultravioletglue to form a Fabry-Perot cavity. The Fabry-Perot cavity and the single-mode fiber Bragg grating are cascaded to form the sensing structure. The Fabry- Perotcavity is sensitive to temperature and refractive index ,while the fiber Bragg grating is sensitive to temperature but not to refractive index. Using the above characteristics ,the sensitivity matrix method can be used to achieve simultaneous measurement of temperature and refractiveindex. Experimentalresultsshow thatthe temperatureand refractiveindex sensitivities of the sensor are - 0. 4832 nm/℃ and - 508. 64 pm/RIU ,respectively. The sensor has the characteristics of a simple manufacturing process ,compact structure ,low cost ,and high sensitivity ,and has good application prospects..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 349 (2024)
Study of Autozeroing Low-noise CTIA Readout Circuit
YANG Jingxin, ZHONG Jiaxin, OUYANG Xuelong, KONG Dalin, and YUAN Honghui
Infrared detectors have diverse applications in the defense and aerospace fields ,and they rely on low-noise readout circuits for acquiring useful and clear infrared images. Detectors operating under high-background and weak-signal scenarios encounter issues such as substantial noise disturbances ,uneven signals acrossInfrared detectors have diverse applications in the defense and aerospace fields ,and they rely on low-noise readout circuits for acquiring useful and clear infrared images. Detectors operating under high-background and weak-signal scenarios encounter issues such as substantial noise disturbances ,uneven signals across elements ,and unreadable signals. To satisfy the requirements for the application of infrared detectors in aerospace engineering in China ,we designed a novel low-noise readout circuit based on the traditional capacitive transimpedance amplifier ( CTIA) in this study. The circuit design utilized autozeroing technology and a new correlation double-sampling circuit with excellent noise suppression capability. We applied the proposed circuit to signal readouts in common midwave line-array infrared HgCdTe spacedetectorsand otherlow-and normal-temperaturedetectorswith operating temperatures within77~ 300K. Further ,we performed simulation verification ,followed by the tape-outof a 10× 1 line-array readout circuit using a 0. 35μm 5 V CMOS process. Our results showed a total output noise of 72. 1 μV ,which was 44. 7% lower than that of the traditional CTIA circuit..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 356 (2024)
Tunable Anisotropic Absorber Based on Multilayer Graphene-Black Phosphorus Structure
XIAO Gongli, LAIZifan, YANG Hongyan, LIN Zhixiong, LIHaiou, and CHEN Zanhui
Based on impedance matching theory and the multilayer local surface plasmon resonance coupling effect ,we designed a multilayer graphene-black phosphorus tunable anisotropic absorber. We used the finite-difference time-domain method to simulate and analyze the results. Under TE polarization ,we achieved an average broaBased on impedance matching theory and the multilayer local surface plasmon resonance coupling effect ,we designed a multilayer graphene-black phosphorus tunable anisotropic absorber. We used the finite-difference time-domain method to simulate and analyze the results. Under TE polarization ,we achieved an average broadband absorption of94% in the wavelength rangeof20. 8~45. 34μm. UnderTM polarization ,weachieved an averagebroadband absorption of96. 3% in the wavelength range of16. 6~44. 6 μm ,thus indicating a certain degree of anisotropic absorption. In addition ,the absorption bandwidth can be altered by adjusting the width of the graphene-black phosphorus block. Simultaneously ,dynamically adjusting the Fermi level of graphene or the electron-doping concentration of black phosphorus can alter the absorption bandwidth and average absorption rate. The results of this study are theoretically significant in the fields of dynamic tunable infrared-energy acquisition ,polarization-selective absorption ,and infrared camouflage..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 362 (2024)
Numerical Simulation of CIGS Thin-Film Solar Cells
CHEN Jinfu, WANG Li, DONG Zhihu, CAIYang, QIN Xinyu, and HE Chunqing
Thisstudyinvestigatesvariouscopper-indium-gallium-selenium (CIGS) thin-film solar cells by adjusting the Ga component ratio ,defect density ,thickness ,and doping concentration of the absorption layer in simulations using the SCAPS software. The results are correlated with the carrier generation rate ,energy band alignThisstudyinvestigatesvariouscopper-indium-gallium-selenium (CIGS) thin-film solar cells by adjusting the Ga component ratio ,defect density ,thickness ,and doping concentration of the absorption layer in simulations using the SCAPS software. The results are correlated with the carrier generation rate ,energy band alignment ,and electric field. The simulations indicate that for a thin-film solar cell prepared via single-step co-evaporation ,the energy-spike-like band alignment of the CIGS/CdS heterojunction facilitates carrier transport ,resulting in excellentoutput performance when the Ga content is30%. In contrast ,the output performance of a solar cell prepared via three-step co-evaporation exceeds that of a solar cell prepared via single-step co-evaporation due to the lower defect density of its absorption layer. Increasing the thickness of the absorption layer causes the 2. 0 μm-thick layer to absorb most ultraviolet-visible lightphotons ,butfurther increases decrease the short-circuit currentdensity. Moreover ,the open-circuit voltage and optovoltage of the solar cell increase with doping concentration ,while the short-circuit current and potential barrier of the CIGS/CdS heterojunction decrease. By optimizing the thin-film solar-cell parameters ,the photovoltaic conversion efficiency of the CIGS thin-film solar cellreached a maximum of27. 67%..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 369 (2024)
Structure Design and Characteristics Research of 1000 V 4H-SiC VDMOS
LIYao, NIU Ruixia, WANG Ailing, WANG Fenqiang, LAN Jun, ZHANG Xuying, ZHANG Pengjie, LIU Liangpeng, and WU Huizhou
This studyfocuseson designing and optimizing a1000V verticaldouble-diffusion metal oxide semiconductor (VDMOS) field-effect transistor using 4H-SiC. Leveraging Silvaco simulation software ,we comprehensively investigate the relationship between device parameters and withstand voltage characteristics ,aiming for a 50% mThis studyfocuseson designing and optimizing a1000V verticaldouble-diffusion metal oxide semiconductor (VDMOS) field-effect transistor using 4H-SiC. Leveraging Silvaco simulation software ,we comprehensively investigate the relationship between device parameters and withstand voltage characteristics ,aiming for a 50% margin. Following optimization ,the device achieves a threshold voltage of 2. 3 V ,with the breakdown voltage reaching 1 525 V. Compared with an Si-basedVDMOS underidenticalwithstand voltageconditions ,the breakdown voltage of the 4H-SiC VDMOS increases by12%. Notably ,the surface electric fielddistribution of the4H-SiC VDMOSduringbreakdown remainsrelatively uniform ,with a maximum value of3. 4× 106 V/cm. The effective terminal length measures at 15 μm ,approximately 6% that of an Si- basedVDMOS ,with the overall area reducing by nearly 1/10. Furthermore ,the structure is simpler compared to thatofthe4H-SiC VDMOS underidenticalwithstand voltage conditions. It involves no additionalprocess steps ,thus facilitating easy device fabrication..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 378 (2024)
Frequency Stability of Optoelectronics Based on Optoelectronic Hybrid Feedback Control
JIANG Yuzhou, PENG Yubin, and YU Caibin
Optoelectronic oscillators have been extensively investigated for military and civilian applications owing to their low phase noise and adjustable frequency. However ,they exhibitunstable output-signal frequencies ,which limits their application and widespread use in engineering. Hence ,this study investigates the freqOptoelectronic oscillators have been extensively investigated for military and civilian applications owing to their low phase noise and adjustable frequency. However ,they exhibitunstable output-signal frequencies ,which limits their application and widespread use in engineering. Hence ,this study investigates the frequency-drift mechanism of optoelectronic oscillators and proposes a frequency-stabilization method for optoelectronic oscillators based on photoelectric hybrid feedback control. This method can realize a stable output under a specific oscillation frequency of a photoelectric oscillator while ensuring low phase noise from the optoelectronic oscillator. Experimental test results show that the stability of the photoelectric oscillator can reach 5. 6× 10- 12 daily ,which satisfies the application requirement for frequency stabilization in engineering..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 384 (2024)
A High-Speed,Digitized,3D-Integrated CCD-CMOS Image Sensor
LIMing, HUANG Fang, LIU Geyang, ZHOU Hourong, WANG Xiaodong, and REN Siwei
An integrated CCD-CMOS image sensor with an array size of 1 024× 256 is proposed in this paper to meet the need for high-precision digitization and high-speed output of CCD image sensor signals. Technologies related to CCD pixel device structure ,CMOS readout circuit ,3D integration with heterogeneous interconnectAn integrated CCD-CMOS image sensor with an array size of 1 024× 256 is proposed in this paper to meet the need for high-precision digitization and high-speed output of CCD image sensor signals. Technologies related to CCD pixel device structure ,CMOS readout circuit ,3D integration with heterogeneous interconnection ,and high-density pin packaging were developed to address issues such as low compatibility between CCD and CMOS processes ,the complexity ofintegration byinterconnection ,thereby achieving both adequate matching and high performance at connection ports between circuit dies. This new image sensor realizes the combination of high-precision CCD signal digitization ,high-speed output ,and multiple dies integration ,filling the domesticgap in CCD-CMOS3D integration technology. Testresults show that the CCD-CMOS device has a normal photoresponse and imaging ability ,achieving good imaging results from both array sideswithoutanydark orbroken columns. The connectivity rate of interconnection reaches 99. 9% ,meeting the needs of 3D integration. As an integrated detector device ,it offers large full well capacity and high sensitivity imaging (FWC e- count reaching 165. 28ke- ,peak QE reaching 86. 1%) ,high-precision digitization(12bit) ,and high- speed output(row readout frequency reaching 100. 85kHz) ,thus meeting the requirements of integrated ,digitized ,miniaturized multispectral detecting and imaging systems..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 388 (2024)
Research on Dual-Color Digital ROIC forIRFPA
JIANG Yu, LIANG Qinghua, LU Tian, and DING Ruijun
In this study ,we designed an infrared focalplane array (IRFPA) digitalreadout integrated circuit (ROIC) for medium/long-wave (MW/LW) dual-color applications. Owing to the variation in the magnitude of the injection current ,dynamic output impedance of dual-color IRFPA devices ,and the high sensitivity required for botIn this study ,we designed an infrared focalplane array (IRFPA) digitalreadout integrated circuit (ROIC) for medium/long-wave (MW/LW) dual-color applications. Owing to the variation in the magnitude of the injection current ,dynamic output impedance of dual-color IRFPA devices ,and the high sensitivity required for both bands ,the structural design of two inputstages and a large dynamic range must be achieved within the limited pixel area of the ROIC. Therefore ,the proposed circuit adopted a pulse frequency modulation (PFM) structure based on a directinjection (DI) type inputstage and a charge resetunitto replace the traditional voltage reset structure ,reducing the detectable charge resolution and improved the nonlinear effect caused bytheresetlostcharge. We designed a20-bithybrid structurecounterto satisfythe large-charge capacity and low-power consumption requirements of the circuit. Simulation results demonstrated thatthe minimum chargeresolution was692e- ,corresponding to a chargecapacity of0. 72Ge. The dual-band detection linearity exceeded 99. 8% ,and the power consumption was 3. 03/6. 66μW in typicalMW/LW applications..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 395 (2024)
Self-sealing Integrated Photodetector Module for Broadband Phased Array Systems
WANG Maoxu, TANG Zhenhua, YU You, LIU Ting, XIAO Yongchuan, and QU Pengfei
In this study ,we developed a self-sealing miniaturized photoelectric detection module based on a low-temperature co-fired ceramic (LTCC) substrate. We confirmed that the module facilitates the rapid sealing of devices through the heating of the embedded resistance of the LTCC. It supports the internal integration of mIn this study ,we developed a self-sealing miniaturized photoelectric detection module based on a low-temperature co-fired ceramic (LTCC) substrate. We confirmed that the module facilitates the rapid sealing of devices through the heating of the embedded resistance of the LTCC. It supports the internal integration of multi-functional optoelectronic chips and enabled planar and surface-mount mounting with external units; therefore ,the module exhibits enhanced installation adaptability and reliability. Test results showed that the module has high responsiveness and flatness in the 18GHz frequency range ,with its volume reduced by an order ofmagnitude compared to thatofa discretedevice. The costofthe moduleisexpected to decrease by more than half ,making itsuitable for a wide range of applications in broadband phased array systems on airborne ,spaceborne ,missile-borne ,and other platforms..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 401 (2024)
Design of Wavelength Modulation PMMA Optical Waveguide SPR Sensing Structure for Refractive Index Sensing
YU Yonghao, ZHOU Shengchao, ZHANG Meiling, ZHANG Rong, and KONG Mei
Optical-waveguide surfaceplasmon resonance (SPR) sensorsarecharacterized by smallsizes ,label-freedetection capabilities ,and easeofintegration. In this study ,wedesigned a poly(methyl methacrylate) ( PMMA) ridge waveguide SPR sensor sensitive unit based on a wavelength modulation method and optimized its key parameterOptical-waveguide surfaceplasmon resonance (SPR) sensorsarecharacterized by smallsizes ,label-freedetection capabilities ,and easeofintegration. In this study ,wedesigned a poly(methyl methacrylate) ( PMMA) ridge waveguide SPR sensor sensitive unit based on a wavelength modulation method and optimized its key parameters. Our analysis results showed thatthe sensor could operate stably within a liquid-refractive-index testing range of1. 33~ 1. 45. In the high-refractive-index detection region ,the sensorexhibited a sensitivity ofup to 10220nm/RIU and ahigh quality factor of173RIU- 1 ..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 406 (2024)
MSM Blue-Light Photodetector with Unilateral Recessed Electrode Structure
LI Bin, ZHANG Zhenhua, and WEI Jingting
To improve the performance of InGaN-based visible light detectors ,a unilateral recessed interdigital electrode MSM-type blue light photodiode based on a GaN/InGaN MQWs epitaxial materialis fabricated and measured. The I-V characteristic measurement results of the device show that ,compared with traditional planar elecTo improve the performance of InGaN-based visible light detectors ,a unilateral recessed interdigital electrode MSM-type blue light photodiode based on a GaN/InGaN MQWs epitaxial materialis fabricated and measured. The I-V characteristic measurement results of the device show that ,compared with traditional planar electrode devices ,recessed electrode devices have smaller and flatter dark currents and larger photocurrents with increasing bias. Spectral response measurements show thatthe cutoffband edge ofthe device is located near490nm ,and the rejection ratio at the band edge of the recessed electrode device is one order of magnitude higher than thatof the planar electrode device. At a bias voltage of 5 V ,the responsivity of the recessed electrode device is 0. 034 6 A/W @ 480 nm ,corresponding to an external quantum efficiency of8. 94% ,thatis higher than thatofthe planar electrode device. The improvementin device performance is attributed to the effective suppression of the surface conduction leakage current and the improved distribution of the built-in electric field achieved by the unilateral recessed electrode structure. Thisresultsin a reduced dark currentin the deviceand enhancesthe collection of photogenerated carriers by the electrodes ,thereby increasing the responsivity..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 410 (2024)
Neutron Detectors Based on Large-Thickness Hexagonal Boron Nitrides
LIU Jingrun, CAO Yan, LIU Xiaohang, FAN Shengda, WANG Shuai, CHEN Xi, LIU Hongtao, LIU Yancheng, ZHAO Jiangbin, HE Gaokui, and CHEN Zhanguo
In thisstudy ,weprepareahigh-quality203μm-thick hexagonalboron nitride (h- BN) ( which is neuron-sensitive) using low-pressure chemical vapor deposition at 1 673 K ,achieving a growth rate of approximately 20 μm/h. We fabricate h-BN neutron detectors with vertical structuresbydepositing100nm-thick Au electrodeson both In thisstudy ,weprepareahigh-quality203μm-thick hexagonalboron nitride (h- BN) ( which is neuron-sensitive) using low-pressure chemical vapor deposition at 1 673 K ,achieving a growth rate of approximately 20 μm/h. We fabricate h-BN neutron detectors with vertical structuresbydepositing100nm-thick Au electrodeson both sidesofh-BN. Ourelectrical transport measurement results show that the prepared h-BN material possesses a mobility-life product (μτ) and resistivity of 2. 8 × 10- 6 cm2/V and 1. 5 × 1014 Ω · cm ,respectively. The neutron detectorbased on the203μm-thick h-BN exhibits neutron detection and charge collection efficiencies of34. 5% and 60% ,respectively ,at850V when irradiated by thermalneutrons from Am-Be sources..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 415 (2024)
Preparation and UV Photodetection Properties of a Co3O4/Fe2O3 Heterojunction Composite
LILihua, PENG Shaolong, CONG Wenbo, WANG Hang, WANG Yuxin, and HUANG Jinliang
In this study ,we prepare a Co3 O4 seed layer and thin film on an FTO substrate using spin-coating and hydrothermalmethods ,respectively. Wethen hydrothermallygrow Fe2 O3 nanorods on the Co3 O4 thin film to obtain high-quality Co3 O4/Fe2 O3 heterojunction composite materials. By changing the concentration of the Fe2 O3In this study ,we prepare a Co3 O4 seed layer and thin film on an FTO substrate using spin-coating and hydrothermalmethods ,respectively. Wethen hydrothermallygrow Fe2 O3 nanorods on the Co3 O4 thin film to obtain high-quality Co3 O4/Fe2 O3 heterojunction composite materials. By changing the concentration of the Fe2 O3 precursor solution ,we can alter the contents of the Fe2 O3 components in the heterojunction composite materials. Results indicated thatFe2 O3 nanorods covered the Co3 O4 thin film with a network structure. With an increase in the Fe2 O3 precursor solution concentration ,the response of the Co3 O4/Fe2 O3 heterojunction composite materialto ultravioletlightgradually increased. When the concentration of the Fe2 O3 precursor solution was 0. 015 mol/L ,the heterojunction composite material exhibited good photoelectric stability ,a high response rate (12. 5 mA/W) ,and a high detection rate (4. 4×1010 Jones) ..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 420 (2024)
Transient Characteristics of A Two-stage Thermoelectric Cooler with An Internal Heat Sourcein A Confined Space
XU Chenxin, CHEN Zhaojun, and MENG Fankai
In this study ,we established transient performance calculation models for air- cooled and heat pipe two-stage thermoelectric cooler devices operating in confined spaces with internal heat sources. We determined the variation laws of the cooling space temperature ,temperature differencebetween thetwojunctionsofthe moduIn this study ,we established transient performance calculation models for air- cooled and heat pipe two-stage thermoelectric cooler devices operating in confined spaces with internal heat sources. We determined the variation laws of the cooling space temperature ,temperature differencebetween thetwojunctionsofthe module ,and cooling coefficientwith time as wellas compared the effects ofthe two heatdissipation methods on the device characteristics. We analyzed the effects of the operating current ,thermocouple two-stage area ratio ,and thermocouple leg length ratio on the temperature ,elapsed time ,and cooling coefficient. Our results showed thatfor an internal heat source power of6 W ,the temperatures of the air-cooled and heatpipe coolers were 8. 28 and 7. 86 ℃ higher than that observed without a heat source. Furthermore ,the cooling temperature of the heatpipe cooler was 1. 85℃ lower than that of the air- cooled cooler ,whereasits cooling coefficientwas 12. 12% higherthan thatofthe air-cooled cooler..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 426 (2024)
Process of Etching Shallow Tapered-Hole Arraysin Quartz Glass
WU Liying, LIU Dan, QUAN Xueling, CHENG Xiulan, ZHANG Zhiqi, GAO Qingxue, FU Xuecheng, XU Liping, ZHANG Wenhao, and MA Ling
We herein introduce a method for preparing shallow-tapered holes etched on quartz glass. The effects of lithographic and etching parameters (gas flow ,gas composition ,cavity pressure ,ICP power ,and bias power) on the etching properties ,surface profile ,etching rate ,and sidewallinclination ofquartz glass were investWe herein introduce a method for preparing shallow-tapered holes etched on quartz glass. The effects of lithographic and etching parameters (gas flow ,gas composition ,cavity pressure ,ICP power ,and bias power) on the etching properties ,surface profile ,etching rate ,and sidewallinclination ofquartz glass were investigated. The results showed thatthe type of etching gas significantly affected the etching of the shallow cone-hole array on quartz and that the combination ofCF4 andAryielded thebestetching effect. As theCF4 gasflow rateincreased ,the quartzetching angle firstdecreased and then increased slightly. When the CF4 ∶ Argas flow ratiowas5 ∶ 3 ,the quartzetching ratewas0. 154μm/min ,the photoresistetching rate was0. 12μm/min ,and the inclination of the shallow quartz cone hole was the highest. When other etching parameters were applied ,the ICP power increased from 600 to 800W ,the quartz etching rate decreased significantly ,and polymer deposition became the dominant etching process. The roughness (Rq ) of the etched quartz increased with decreasing ICP power. As the RF power increased ,the rate of quartz etching increased ,and the Rq value of the etched quartz first increased and then decreased. When the RF power was increased to 200 W ,photoresist carbonization occurred. This study provides a technical reference for the preparation of quartz- glass microdevices..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 434 (2024)
Enhanced Two-photon Fluorescence of CsPbBr3 Nanocrystal Superlattice on Gold Films
WEN Yongxiang, YU Ying, and LIU Shaoding
Two-photon fluorescence emitted by micro/nanostructured perovskites has been widely applied in high-resolution imaging and photoelectric conversion. However ,significantly enhancing the two-photon fluorescence emission intensity is essential for improving the performance of associated devices. Unlike dielectric substraTwo-photon fluorescence emitted by micro/nanostructured perovskites has been widely applied in high-resolution imaging and photoelectric conversion. However ,significantly enhancing the two-photon fluorescence emission intensity is essential for improving the performance of associated devices. Unlike dielectric substrates ,the development of micro/ nanostructures on precious metal films is effective for achieving enhanced linear and nonlinear opticalresponsesowing to plasmon excitation. The results of this study showed thatthe optical response of superlattice structuresgrown on a goldfilm was strongerthan thatofsamplesgrown on a glass substrate. Furthermore ,experimental results showed that the linear photoluminescence intensity increased by approximately100% and the two-photon luminescence intensityincreased significantlybyapproximately16times. Furthermore ,weconfirmed a distinct polarization dependence of the two-photon emission of this superlattice by changing the polarization of the pump light ,and that the polarization angle exhibited quadruple symmetry within the range of 0°~ 360°. These results indicated that growing a CsPbBr3 nanocrystalline superlattice on a gold film is an effective strategy to achieve enhanced two-photon emission intensities. This study provides new possibilities and optimization ideas for constructing high- performance micro/nano-nonlinear photonic devices..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 442 (2024)
Indoor Visible-light Localization Based on Received Signal Strength Ratio using Fused RNGO-Elman Neural Network
ZHANG Huiying, SHENG Meichun, LIANG Shida, MA Chengyu, and LIYueyue
Aiming at the problems of low positioning accuracy and poor stability of traditional visible-light positioning methods based on the strength of the received signal in dynamic environments ,this paper proposes an indoor visible-light positioning system using an improved northern goshawk optimization ( NGO) algorithm fusAiming at the problems of low positioning accuracy and poor stability of traditional visible-light positioning methods based on the strength of the received signal in dynamic environments ,this paper proposes an indoor visible-light positioning system using an improved northern goshawk optimization ( NGO) algorithm fused with an optimized Elman neural network (RNGO-Elman) based on the received signalstrength ratio (RSSR) . Thisarticle proposes selecting an auxiliary reference point ,using the RSSR of the testreference pointto the auxiliary reference pointand the trueposition ofthe receiverasthe training setdatato establish a fingerprintdatabase that is not affected by a dynamic environment. Aiming at the problems of NGO algorithms such as slow convergence speed and tendency to fallinto local optimums ,the refractive reverse learning strategy was used to initialize the population ,increase its diversity ,and introduce nonlinear weighting factors to accelerate the convergence speed and avoid falling into localoptimums. The improved NGO algorithm was used to optimize the initialweights and thresholds of the Elman neural network and construct the RNGO-Elman dynamic localization prediction model. The simulation results show that under an experimental space of4 m × 4 m × 3 m ,the optimized RNGO-Elman localization modelhad an averagelocalization errorof1. 34cm ,and the localization accuracy was improved by 82% and 21% compared with the Elman localization algorithm and the NGO-Elman localization algorithm ,respectively. When the LED emission powerfluctuated ,the positioning errorsofthe RNGO-Elman modelbased on the RSSR were 1. 29 and 1. 38cm. The proposed visible lightpositioning method hasthe advantagesofhigh positioning accuracy and stable positioning performance..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 449 (2024)
Phase Iteration Algorithm and Single-Pixel Phase Imaging without Interferometry
CHEN Zhi, FAN Xiaoyan, YUAN Tiantian, and CHEN Wenjie
Single-pixelimaging offersa meansofovercoming the constraintsimposed bythe limited number of pixels in conventional imaging. The realization of phase imaging in a single- pixel framework with consistent stability and optimal accuracy remains challenging. In this study ,we propose single-pixel phase imaging without inteSingle-pixelimaging offersa meansofovercoming the constraintsimposed bythe limited number of pixels in conventional imaging. The realization of phase imaging in a single- pixel framework with consistent stability and optimal accuracy remains challenging. In this study ,we propose single-pixel phase imaging without interferometry and a phase iteration algorithm. The proposed methodology relies on extracting the zero-orderintensity ofthe Fourier spectrum and experimentally achieves a repetition accuracy and error rate of 0. 12% and 4. 1% ,respectively. These experimental findings indicate that our approach exhibits commendable stability and high accuracy and therefore holds great significance for single-pixel imaging developmentand classicalphase imaging innovation..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 458 (2024)
Design of An Infrared FocalPlane Special Shaped Readout Circuit with High Sensitivity and Dynamic Range
QIAO Boquan, WANG Hongyi, JING Song, HUANG Songlei, and GONG Haimei
We designed a new type of infrared focal plane readout circuit with combined pixels to meet the development requirements of both high sensitivity and high dynamic range. The designed circuit can be used for shortwave infrared focal plane detector arrays. Traditional pixels typically use only one inputstage ,which makesWe designed a new type of infrared focal plane readout circuit with combined pixels to meet the development requirements of both high sensitivity and high dynamic range. The designed circuit can be used for shortwave infrared focal plane detector arrays. Traditional pixels typically use only one inputstage ,which makes itdifficultto balance high sensitivity and high dynamic range. In contrast ,combined pixels use a capacitive trans-impedance amplifier (CTIA) input stage along with a high dynamic range input stage ,thereby inheriting their advantages. The specific layoutof a combined pixel contains one high-dynamic-range input stage located in the middle of every 2× 2 CTIA high-sensitivity input stage. This high dynamic range input stage can be switched between direct injection and logarithmic modes. We realized the layout ofa320× 256 readoutcircuitforcombined pixelarrayswith a 15μm pitch using a0. 18μm 3. 3 V standard CMOS process . Simulation results show that both high sensitivity and a high dynamic range can be achieved using small integral capacitors and a high dynamic range in combination with the logarithmic mode..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 463 (2024)
Low-power Face Detection Acceleration System Based on theZynq Platform
ZHAO Min, XU Sheng, HAN Luyu, and LIN Zhixian
To address the issues of large size and high power consumption in CPU- and GPU-based convolutional neural network platforms ,we designed and implemented a convolutional neural network-assisted face detection acceleration system based on the Zynq platform in this study. We adopted the YOLOv3-Tiny algorithm for the propoTo address the issues of large size and high power consumption in CPU- and GPU-based convolutional neural network platforms ,we designed and implemented a convolutional neural network-assisted face detection acceleration system based on the Zynq platform in this study. We adopted the YOLOv3-Tiny algorithm for the proposed system and used the WIDER FACE dataset for training. To improve the network efficiency ,we utilized a layer-fusion technique for reducing the network depth and accelerating detection. Moreover ,we employed an 8-bit integer quantization strategy to minimize memory access and resource consumption. We designed a reusable multichannel convolution computation module by leveraging the parallel computing capability of field-programmable gate arrays (FPGAs) on the ZynqXC7Z035 chip to reuse the digitalsignalprocessor(DSP) . The experimentalresults showed that our designed acceleration system ,which could achieve a real-time inference speed of 9. 5 FPS ,was 7. 9 times faster than intel i7-8700CPU and consumed only 2. 65 W of power ,satisfying the performance requirementof low power consumption..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 469 (2024)
LineLoss Calculation Method forLow-voltage Substations Based on K-Means++ and Elman Neural Networks
ZHANG Linshan, LIAO Yaohua, WANG En, LIBo, ZHU Mengmeng, and WANG Yi
To address theoretical challenges and accuracy limitations in estimating line losses for low-voltage substations ,arising from complex transmission lines ,multiple users ,and data acquisition difficulties ,we devised an innovative calculation approach in this study. Our method merges an enhanced K-means+ + algorithm wiTo address theoretical challenges and accuracy limitations in estimating line losses for low-voltage substations ,arising from complex transmission lines ,multiple users ,and data acquisition difficulties ,we devised an innovative calculation approach in this study. Our method merges an enhanced K-means+ + algorithm with an Elman neural network. We initially conducted an in-depth analysis of factors influencing line losses in low-voltage substations and identified key indicators through correlation analysis. Employing principal component analysis (PCA) ,we reduced data dimensionality and complexity. Utilizing an enhanced K-means+ + algorithm ,we efficiently clustered the dataset and optimized model training. Integration of particleswarm optimization algorithmsfurtherboosted the Elman neuralnetworks,performance. Simulation verification using actual data affirmed the method,s superior performance in training efficiency and computationalaccuracy..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 477 (2024)
Differential ChaosShift Keying System with M-ary Short Reference Permutation Index
LIU Sujie, YANG Liejun, and XIE Zhaopeng
To solve the problem of the low energy efficiency of permutation index differentialchaos shift keying (PI-DCSK) communication systems that employ short-reference technology ,we developed an M-ary short-reference PI-DCSK ( SR-PI-DCSK) system. We shortened the chaotic sequence of the reference timeslotto less than halfofTo solve the problem of the low energy efficiency of permutation index differentialchaos shift keying (PI-DCSK) communication systems that employ short-reference technology ,we developed an M-ary short-reference PI-DCSK ( SR-PI-DCSK) system. We shortened the chaotic sequence of the reference timeslotto less than halfofa symbolperiod and confirmed thatthe information time slot copied and spliced the permutation arrangement of the reference timeslot P times. We analyzed the energy efficiency of the SR-PI-DCSK system and derived its BER expression in a multipath Rayleigh fading channel. Further ,we verified the accuracy of the theoretical derivation using Monte Carlo simulations. The simulation results indicate thatcompared with the PI-DCSK system ,the proposed system has a betterperformance gain under the same conditions ,thus providing a candidate chaotic modulation scheme for the nextgeneration of short-range communication applications in the Internet of Things (IOT) . Moreover ,the system can effectively improve the energy efficiency and bit error rate (BER) of the PI-DCSK system withoutincreasingits structuralcomplexity while requiring the sameenergy to recover the bitinformation..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 485 (2024)
Asphalt Road Crack Detection Method Based on Improved Deep Labv3+ Network
CHEN Changchuan, HAO Xiaoyan, LONG Hongyu, and SUN Xia
A semantic segmentation method based on an improved DeepLabv3+network is proposed to address the issues of low detection accuracy and large errors associated with traditional semantic segmentation techniques for detecting asphalt road cracks. In the encoder stage ,this method replaces the backbone network Xception of DA semantic segmentation method based on an improved DeepLabv3+network is proposed to address the issues of low detection accuracy and large errors associated with traditional semantic segmentation techniques for detecting asphalt road cracks. In the encoder stage ,this method replaces the backbone network Xception of DeepLabv3+ with lightweight MobileNetv2 ,thereby reducing the numberofparameters. In the decoderstage ,a dualattention mechanism is incorporated to further improve the segmentation accuracy of the network. The Dice loss function is combined with the original cross-entropy loss function to alleviate the imbalance between foreground and background in the sample. Extensive experiments were conducted on real-time road detection data. The results indicate that ,compared with the original DeepLabv3+ ,the averageintersection-to-union ratio (mIoU) and average pixelaccuracy (mPA) achieved bythe proposed method werehigherby8. 98% and 17. 39% ,respectively. As compared with other mainstream semantic segmentation models ,the improved DeepLabv3+ also exhibits good performance in detecting asphaltroad cracks..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 493 (2024)
Multiscale Target Detection for UAV Aerial Images
JIA Liang, LIN Mingwen, QILijin, and TAN Jin
A multiscale target detection network,VTO-YOLOv8,for unmanned aerial vehicle (UAV) images is proposed to address the low accuracy of existing algorithms caused by complex backgrounds,a high proportion of smalltargets,and uneven distributions.First,wise intersection over union (WIoU) v3 was used as the bounding-box regrA multiscale target detection network,VTO-YOLOv8,for unmanned aerial vehicle (UAV) images is proposed to address the low accuracy of existing algorithms caused by complex backgrounds,a high proportion of smalltargets,and uneven distributions.First,wise intersection over union (WIoU) v3 was used as the bounding-box regression loss,and a wise gradient allocation strategy was employed for the network to focus more on regular quality samples and improve localization ability.Second,a four-layer target bi-directional feature pyramid network (T-BiFPN) structurewas designed to strengthen the integration ofshallow and deep features.Furthermore,a faster implementation of CSP bottleneck with diverse branch blocks (C2f-DBB) module was designed to improve the detection performance of the network withoutincreasing computationalcomplexity.In addition,a focalmodulation module wasused to enhance the interaction ofinformation atdifferentscales.The experimentalresults demonstrated thatthe proposed network improved the mean average precision (mAP) and mAP50 by 5.9% and 9.0%,respectively,compared with those of the baseline network on the Visdrone2019 dataset.Moreover,the network parameters were reduced by 22.6%.The proposed method can be applied to targetdetection in UAV aerialphotography..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 501 (2024)
Pavement Crack Feature Extraction Based on Image Processing
DAI Shaosheng, MAO Xinghua, and YU Zian
Cracks area common type of pavement damage.Thus,the accurate and timely detection and evaluation ofthe statusofpavementcracks arecrucialforroad condition monitoring and maintenance decision-making.This study proposes a pavement crack feature extraction method based on image processing.First,we performed a connected-domCracks area common type of pavement damage.Thus,the accurate and timely detection and evaluation ofthe statusofpavementcracks arecrucialforroad condition monitoring and maintenance decision-making.This study proposes a pavement crack feature extraction method based on image processing.First,we performed a connected-domain analysis on the segmented pavement binary image,whereby the connected domains representing cracks were selected based on the feature differences between the crack and interference regions.Subsequently,we applied an improved fast parallel-thinning algorithm to extract the crack skeleton,and the branch length of the endpointwas used as the standard to remove burrs in the skeleton.To address the problems of skeletal fracture and inward shortening,we used the direction of the endpoints and the distance between them to connectand grow the skeleton.The experimentalresults show that this method can effectively remove interfering regions from the segmentation results,thereby extracting a clear and complete single-pixel skeleton of cracks withoutburrs to betterreflectthe main structuraland morphologicalcharacteristicsofthe crack..
Semiconductor Optoelectronics
- Publication Date: Oct. 15, 2024
- Vol. 45, Issue 3, 508 (2024)
© Copyright 2018-2021 | Chinese Laser Press. All Rights Reserved 沪ICP备15018463号-20