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1.
雪崩光电二极管由于具有高增益特性而广泛应用于激光测距机中,但由于在电流倍增过程中引入的高附加噪声,使激光测距机进一步提高信噪比遇到了瓶颈。石墨烯具有高电子迁移率、零带隙结构、独特光吸收系数等特性使其广泛应用于激光器、光调制器、透明电极以及超快光电探测器。该研究提出了一种高信噪比的谐振腔型石墨烯光电探测器的设计方法。以波长为1.06μm的激光为例,采用光学传输矩阵法和散射矩阵法,研究了光波在谐振腔传输和吸收层吸收的机理,建立了谐振腔型光电探测器的光吸收模型,通过优化,器件最终量子效率达到91.2%,响应度达到0.778A·W~(-1),半高全宽达到6nm;分析石墨烯在谐振腔中的位置对器件吸收率的影响,发现在满足谐振条件下,器件吸收率随石墨烯位置呈现周期性变化,腔长的改变不改变吸收率峰值,而是改变了吸收率峰值对应的石墨烯在谐振腔中的位置,当腔长是入射光半波长的n倍时,随着石墨烯位置变化,将出现2n个吸收率峰值,且关于谐振腔中心点对称分布;选择石墨烯距顶层反射镜0.402 8μm时,器件吸收率达到94%,相比单层石墨烯,吸收率提高了16dB;通过对比求解谐振腔型石墨烯光电探测器和雪崩光电二极管信噪比方程,得出谐振腔型石墨烯光电探测器信噪比可达到90.3,较雪崩光电二极管提高了10dB;理论分析表明,谐振腔型石墨烯光电探测器具有高吸收率、高量子效率和高信噪比,研究成果将对激光测距机接收系统中光电探测器的更新设计和应用提供理论参考。  相似文献   

2.
本文采用P3HT∶PTB7∶PC61BM为活性层,制备了覆盖可见光范围的三元体异质结有机光电探测器(organic photodetectors,OPDs).利用原子力显微镜、紫外可见吸收光谱和荧光光谱等手段研究了PTB7添加到P3HT∶PC61BM体系中对OPDs光学和电学性质的影响,发现当P3HT∶PTB7∶PC61BM的质量比为8∶2∶10时,三元混合层的响应光谱扩展到780 nm,OPDs的响应度R在630,530,460 nm的光照和–1 V偏压下分别达到178,291,241 mA/W,比探测率D*达到1012 Jones,并与课题组之前成果P3HT∶PBDT-TT-C∶PC61BM为活性层的三元有机光电探测器做了对比.分析了两种基于苯并[1,2-b∶4,5-b]二噻吩(BDT)单元的聚合物PTB7与PBDT-TT-C分别添加到同一体系P3HT∶PC61BM中产生的器件性能差距的现象,解释了PTB7由于氟原子的引入,对混合薄膜微观形貌的影响和对薄膜中光生载流子迁移率的提升的原因.这为制备性能更好的有机光电探测器提供了理论依据和方法.  相似文献   

3.
采用P3HT∶PBDT-TT-C∶PC_(61)BM为活性层,通过溶液旋涂和高真空蒸镀工艺制备了覆盖可见光范围的高探测率有机光电探测器.利用原子力显微镜、紫外可见吸收光谱和荧光光谱研究了窄带隙聚合物红光吸收材料PBDT-TT-C掺入P3HT∶PC_(61)BM对活性层薄膜光学特性和器件电学特性的影响.研究发现当活性层中P3HT∶PBDT-TT-C∶PC_(61)BM质量比为8∶2∶10时,活性层的响应光谱范围拓宽到350~780 nm.其探测器在-1 V偏压下红绿蓝三基色的光响应度和外量子效率分别达到了422 mA/W、464 mA/W、286 mA/W和83%、108%、77%,比探测率均达到10~(12)Jones以上.结果表明,在有机光电探测器活性层中掺入吸收光谱互补的有机材料,在保证薄膜微观形貌的基础上,通过调节三元混合材料的质量比,不仅可以优化载流子的产生和输运,提高器件的光电流,还可通过第三组分的掺入促进薄膜结晶,减小器件的暗电流.  相似文献   

4.
胡红光 《应用光学》2000,21(Z1):53-57
简介一种以锗雪崩光电二极管(APD)为光电转换器件的探测器电路的工作原理,详细介绍电路各组成部分的设计要求和设计要点.该电路可用于光学测距和微弱光的探测装置.  相似文献   

5.
余金中  王杏华 《物理》2002,31(8):527-533
光电探测器是一类用于接收光波并转变为电信号的专门器件,文章描述了PIN光电二极`管雪崩光电二极管、MSM(金属-半导体-金属)光电二极管的器件结构和工作原理,并对它们的响应度、噪声、带宽等特性进行了讨论,这类器件已在光通信、光信息处理等许多系统中得到广泛的应用。  相似文献   

6.
梁振江  刘海霞  牛燕雄  尹贻恒 《物理学报》2016,65(13):138501-138501
提出了一种具有超薄有源层的谐振腔增强型石墨烯光电探测器的设计方法,利用谐振腔结构可以将光场限制在腔内,有效增强探测器的吸收.通过研究谐振腔内光场谐振条件及谐振模式下探测器响应度增强的机理,建立了驻波效应下谐振腔增强型石墨烯光电探测器光吸收模型,仿真分析谐振腔反射镜反射率、谐振腔腔长对于腔内光场增强器件性能的影响.理论分析表明,谐振腔增强型石墨烯光电探测器在850 nm处响应度可达0.5 A/W,相比无腔状态下提高了32倍;半高全宽为10 nm.采用谐振腔结构能够提高石墨烯光电探测器件的光电响应,为解决光电探测器响应度与响应速度之间的相互制约关系提供了途径.  相似文献   

7.
采用溶液法制备了结构为ITO/PEDOT∶PSS/活性层/Al的四元倍增型有机光电探测器,器件本体异质结活性层由P3HT∶PTB7-Th∶IEICO∶PC_(71)BM以90∶10∶0.5∶0.5的质量比共混组成。随着偏压增加,器件外量子效率(External quantum efficiency, EQE)远超100%,并展现300~850 nm的宽光谱响应。在330 nm与780 nm处,器件可获得的最高EQEs和响应度分别为773000%和2 057 A·W~(-1)以及311000%和1 956 A·W~(-1),为有机光电探测器在紫外和近红外光区可获得的最高EQE和响应度之一。-25 V偏压下,与结构为ITO/PEDOT∶PSS/P3HT∶PTB7-Th∶IEICO(90∶10∶1)/Al的三元器件相比,四元器件的平均EQE(388167%)、响应度(1 604 A·W~(-1))以及探测灵敏度(3.6×10~(13) Jones)分别提高了0.5倍、0.5倍和0.4倍,有效提升了器件对弱光的探测能力。上述结果提供了一种制备多元宽带倍增型有机光电探测器的有效策略,用以提高器件弱光探测能力,特别是提升了器件对紫外和近红外光的响应与探测能力。  相似文献   

8.
张戎  郭旭光  曹俊诚 《物理学报》2011,60(5):50705-050705
光栅耦合是量子阱光电探测器探测正入射电磁辐射的常用耦合方法,本文采用模式展开法研究了一维金属光栅太赫兹量子阱光电探测器中的电磁场分布,并给出了器件有源区中的平均光强.研究结果表明,若一维光栅的周期与太赫兹波在器件材料中的波长相当,并且根据器件结构选取合理的光栅占空比,可使器件中的平均光场最强,光栅的光耦合效率最高,从而提高器件的响应率. 关键词: 太赫兹 量子阱光电探测器 光栅  相似文献   

9.
基于UMC 0.18μm CMOS工艺,提出一种适合紫外/蓝光探测的探测器,该器件由栅体互联的NMOS晶体管和横向/纵向光电二极管构成.其中,浅结的光电二极管由UMC工艺中Twell层(浅P阱)和Nwell层形成,以增强其对紫外/蓝光的吸收,栅体互联的NMOS晶体管可以放大光电流,提高探测器的灵敏度和动态范围.仿真结果表明,本文设计的紫外/蓝光探测器具有低的工作电压和暗电流,对300~550nm波长范围的光具有高的响应度和宽的动态范围.在弱光条件下(光强小于1μW/cm2),响应度优于105 A/W,随着光强增大,响应度逐渐降低,但总体仍超过103 A/W.  相似文献   

10.
PIN光电二极管探测器响应特性测试   总被引:1,自引:1,他引:1  
介绍了PIN光电二极管探测器的工作原理及基本结构,设计了探测器的测试系统,说明了测试系统中各个组成部分的结构和功能.利用该系统对PIN管光探测器电路的电特性进行了测试,测试结果表明PIN光电二极管探测器的响应特性符合技术要求.  相似文献   

11.
R.W. Mao  J.Z. Yu 《Optics Communications》2008,281(6):1582-1587
A method for fabrication of long-wavelength narrow line-width InGaAs resonant cavity enhanced (RCE) photodetectors in a silicon substrate operating at the wavelength range of 1.3-1.6 μm has been developed. A full width at half maximum (FWHM) of 0.7 nm and a peak responsivity of 0.16 A/W at the resonance wavelength of 1.55 μm have been accomplished by using a thick InP layer as part of the resonant cavity. The effects of roughness and tilt of the InP layer surface, and its free carrier absorption, as well as the thickness deviation of the mirror pair on the resonance wavelength shift and the peak quantum efficiency of the RCE photodetectors are analyzed in detail, and approaches for minimizing them toward superior performance are suggested.  相似文献   

12.
微腔有机电致发光器件的谐振腔反射镜性能   总被引:3,自引:2,他引:1  
根据微腔原理运用传输矩阵法对构成微腔有机电致发光器件(MOLED)谐振腔的两个反射镜进行模拟计算并比较,可观察到:随金属反射镜的反射率增大,微腔器件的电致发光(PL)谱的半峰全宽(FWHM)逐渐窄化;峰值逐渐蓝移至设计的谐振峰值520nm处;峰值强度和光谱积分强度逐渐增强。结果表明:金属反射镜反射率越大越好。随DBR反射镜的周期数从1增加到9,EL的峰值均为520nm,半峰全宽逐渐窄化,积分强度逐渐减弱;峰值强度由弱增强再减弱,4个周期时峰值强度最大,所以设计微腔器件时,DBR的周期是一项很重要的参数。DBR反射率太大不利于出光,太小微腔效应小。需要根据制作目的和需要进行合理选择。  相似文献   

13.
Wavelength-selective photodetectors employing vertically grating-coupled optical filters are designed with a straightforward waveguide structure in order to improve wavelength selectivity. By arranging stacked layer formation for the absorption layer, we can greatly reduce the cross-talk absorption from unselected light down to -40 dB while keeping high selective absorption efficiency. Such photodetectors with a weighted coupling-assisted grating achieve an excellent bandpass filter-detector response which shows a steep transition between stopband and passband.  相似文献   

14.
1.55 μm低温生长GaAs谐振腔增强型探测器   总被引:4,自引:4,他引:0  
利用低温(200℃)生长的GaAs材料作为吸收层制备了GaAs基1.55 μm谐振腔增强型(RCE) 光电探测器,对其光电特性进行了分析、研究.无光照0偏压下探测器暗电流为8.0×10-12A;光电流谱峰值波长1563 nm;响应谱线半宽4 nm, 具有良好的波长选择性.  相似文献   

15.
In this paper, reflectivity of a Distributed Bragg Reflector (DBR) has been computed by considering the effects of changes of wavelength on the changes of the refractive index of the materials of DBR layers. The intrinsic losses of the materials have been included in the computation of the reflectivity of the DBR. It has been found that the effect of change of the wavelength on the refractive index of the DBR materials reduces the Full Width Half Maxima (FWHM) of the stop band significantly which is expected to improve the laser characteristics. If the FWHM is reduced, the thickness of the active layer of a VCSEL can also be reduced which will further reduce the threshold current of the device. It has been found that the intrinsic losses of the materials have a significant effect on the reflectivity of a DBR. It has also been found that peak reflectivity of a 20 pair AlAs/GaAs DBR reduces by 0.2% after including the intrinsic losses (with a value of the intrinsic losses α = 10 cm?1).  相似文献   

16.
分布布喇格反射镜的反射特性   总被引:2,自引:1,他引:1       下载免费PDF全文
采用等效法布里珀罗(FP)腔方法对分布布喇格反射镜(DBR)的特性进行了研究,计算并讨论了上下两层DBR结构非对称模型反射率的变化.设计了DBR反射镜的反射谱中心波长为850nm的结构.随着DBR周期数的增加,腔反射率峰值逐渐增加.上下两层DBR反射镜的厚度由反射率和中心波长决定.实验表明,下DBR的周期数为30对左右,上DBR的周期数为20对左右,易实现激光输出.非对称的双层DBR的反射特性表明理论计算与实验结果基本一致.  相似文献   

17.
垂直腔面发射激光器的结构生长及特性研究   总被引:1,自引:1,他引:0  
在偏〈111〉A 2°的GaAs (100) 衬底上生长了Al0.9Ga0.1As /Al0.2Ga0.8As周期结构的垂直腔面发射激光器(VCSEL)外延片P 型DBR的周期数为24.5对,N型DBR的周期数为34.5对.用光荧光 (PL) 谱、扫描电子显微镜 (SEM)和X射线双晶衍射 (XRD) 方法对VCSEL的光学特性和结构特性进行了分析室温量子阱材料的PL谱峰值波长为837.0 nm,半高宽达到28.9 nm在X射线双晶衍射回摆曲线中,除了“0”级衍射峰外,还观察到一级和二级卫星峰.“0”级双晶衍射峰的半高宽为12.56弧秒(″),衬底GaAs的衍射峰半高宽为11.79″.“0”级衍射峰半高宽与衬底GaAs的衍射峰半高宽比较接近,表明晶格具有很高的完整性.实验结果表明腔模波长为837.2 nm,腔模波长与PL谱峰值波长相匹配.  相似文献   

18.
A resonant cavity-enhanced (RCE) quantum dot (QD) field-effect transistor (RCEQDFET) is designed for single- photon detection in this paper. Adding distributed Bragg reflection (DBR) mirrors to the single-photon detector (SPD), we improve the light absorption efficiency of the SPD. The effects of the reflectivity of the mirrors, the thickness and light absorption coefficient of the absorbing layer on the detector's light absorption efficiency are investigated, and the resonant cavity is determined by using the air/semiconductor interface as the mirror on the top. Through analyzing the relationship between the refractive index of AlxGal_xAs and A1 component, we choose A1As/Alo.15Gao.85As as the material of the mirror on the bottom. The pairs of A1As/Alo.15Gao.85As film are further determined to be 21 by calculating the reflectivity of the mirror. The detector is fabricated from semiconductor heterostructures grown by molecular beam epitaxy. The reflection spectrum, photoluminescence (PL) spectrum, photocurrent response, and channel current of the detector are tested and the results show that the RCEQDFET-SPD designed in this paper has better performances in photonic response and wavelength selection.  相似文献   

19.
Zi-Heng Wang 《中国物理 B》2022,31(9):98505-098505
To describe the dynamic response characteristics of the laminated graded-bandgap GaAs-based photocathode with distributed Bragg reflection structure, a general theoretical temporal response model is deduced by combining the unsteady continuity equation and numerical calculation method. Through the model, the contribution of the distribution Bragg reflection structure and graded-bandgap emission layer to the temporal response are investigated. Meanwhile, the relationships between the temporal response characteristics of the laminated GaAs-based photocathode and different structural parameters are also analyzed, including average electron decay time, emission layer thickness, and incident light wavelength. It is found that the introduction of distribution Bragg reflection (DBR) layer solves the discrepancy between the absorption capability of the emission layer and the temporal response. Moreover, the distributed Bragg reflection layer can improve the time response by optimizing the initial photoelectron distribution. The improvement effect of the DBR layer on the temporal response is enhanced with the emission layer thickness decreasing or the incident light wavelength increasing. These results explain the effect of the DBR layer of the photocathode on the dynamic characteristics, which can offer a new insight into the dynamic research of GaAs-based photocathode.  相似文献   

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