基于二维材料的快速响应金属-半导体-金属结构光电探测器研究进展

快速响应光电探测器在光通信、高速摄影、生物医学成像等领域有广泛的需求。目前,市场上应用的快速响应光电探测器大多基于硅、砷化镓等传统的无机半导体材料,但是其制作工艺复杂、成本较高,并且机械灵活性差。以石墨烯、二硫化钼为代表的二维材料具有独特的层状结构以及良好的光学、电学、热学和机械特性,是制备光电探测器的理想材料。尤其是部分二维材料所拥有的超高载流子迁移率特性,十分适用于研制快速响应光电探测器。近年来,一系列基于二维材料的金属-半导体-金属结构光电探测器(Metal-semiconductor-metal photodetectors, MSM-PDs)被陆续报道,很多具有1μs以下的快速响应特性。本文以基于二维材料的快速响应MSM-PDs为主题进行综述。首先介绍了MSM-PDs中的基本结构及工作原理,深入剖析了决定其响应速度的主要因素。随后介绍了石墨烯、过渡金属硫化物、黑磷、二维钙钛矿、三元硒氧铋等二维材料的分子结构、光学、电学等特性,并对各类二维材料在MSM-PDs的应用进行对比。然后分类介绍了响应速度在1μs以下的欧姆接触型、肖特基接触型以及基于表面等离激元效应二维材料MSM-PD...     

面向硅基光电子混合集成的二维材料探测器

二维材料因其独特的结构和优异的电子和光电性能,为硅基光电子集成器件提供了新的发展机遇。近年来,面向硅基光电子混合集成的二维材料探测器已被广泛研究。本文梳理了构建光电探测器的几种二维材料基本特性及其探测机制,回顾了基于二维材料的硅光子集成光电探测器研究进展,总结了其器件结构和主要性能指标。最后,讨论了进一步提升硅光子集成二维材料光电探测器性能的策略,包括大规模二维材料集成器件的制备、器件结构与金属接触界面的优化以及新兴二维材料光电探测器的探索,以期推动二维材料在硅基光电子混合集成探测器领域的商业化应用。     

二维材料光电探测器的研究初探

以二维材料的光电探测器为主要研究对象,介绍光电探测器的工作原理,并对多种二维材料光电探测器进行分析,提出增大光吸收率,改良二维材料的制备等改善光电探测器性能的方法。     

不同响应机制下的石墨烯基光电探测器研究进展

光电探测器因可将光信号转换为电信号而被广泛地应用于视频成像、光通信、生物医学成像和运动检测等方面.但由于所采用的传统光电探测器材料对其性能带来的局限性和日益增长的新需求之间的矛盾,使得寻找新的材料迫在眉睫.近年来新兴的二维材料为制备更高性能的探测器提供了全新的材料研究平台,其中石墨烯以其独特的电学、光学与热学特性成为下...     

异质结构在光伏型卤化物钙钛矿光电转换器件中的应用

钙钛矿材料由于具有长的载流子扩散长度、较高的吸收系数和较低的缺陷态密度等优点在太阳电池、光电探测器、发光二极管等光电转换器件领域得到广泛应用.同时,层状二维材料、低维半导体纳米结构、金属纳米结构和绝缘材料等功能材料因它们特殊的化学、电学和物理性质而越来越受到人们的关注.为了拓宽钙钛矿材料在光电转换器件的应用,可将钙钛矿与这些功能材料进行组合,形成异质结构,集成两种材料的优点.钙钛矿/功能材料异质结构可作为界面修饰层、电荷传输层、封装层等应用于卤化物钙钛矿光电转换器件中,用来抑制光生载流子的复合损耗,提升载流子的传输性能,改善器件的稳定性等.本文综述了钙钛矿与层状二维材料、低维半导体纳米结构、金属纳米结构和绝缘材料等形成的异质结构在光伏型光电转换器件中应用的最新研究进展,并对该方向未来的发展做出了展望.     

THzQWP二维光栅耦合效率的理论分析研究

将二维金属光栅结构引入到探测器结构中,以提高太赫兹(THz)量子阱光电探测器的探测率。采用三维时域有限差分算法,建立了THz量子阱光电探测器的二维金属光栅仿真模型,详细分析了二维金属光栅参数对太赫兹量子阱光电探测器的电场强度的影响。仿真分析结果表明:当入射光频率为6.27 THz(相对应波长为47.847 m)、光栅周期P=10.5 m、占空比=0.55（金属块宽度w= 5.755 m）、光栅层厚度h=0.4 m时,器件中的Z方向上的电场值最大,光栅的耦合效率最高。     

低维材料非线性光学与器件专题编者按

正2004年,石墨烯的首次发现为具有独特光子和光电特性的二维材料的发展打开了大门.二维材料通常被称为原子薄层材料,其厚度可减至单层或几层.强的层内共价和弱的层间范德瓦耳斯力是二维材料的典型特征.不同厚度和电子结构的二维材料使其可以在紫外到太赫兹的波长范围内进行光学响应,极大地扩展了二维材料在光子学领域的应用范围.二维材料还具有优异的光子特性,如泡利阻塞诱导的饱和吸收、超快的弛豫时间和高度的光学非线性,为其在光子学领域广泛的应用奠定了基础.由于原子层的二维材料具有机械稳定性和表面自然钝化的特点,可无选择性地牢固地集成到其他结构中,如平面波导、玻璃纤维、光学微腔和其他二维层状结构,而不会出现"晶格失配"问题.此外,二维材料的光学性质可以通过电选通、光激励、或化学掺杂来精确控制.     

亚波长介质光栅对单层过渡金属硫化物的发光增强

过渡金属硫化物单层具有直接带隙,可产生较强的光致发光,这一特殊的性质使其在光电器件、光电探测等领域具有广泛的应用前景.由于只有原子级别的厚度以及存在激子的非辐射复合,其光致发光效率仍有待提高.本文设计了一种金膜-二氧化钛光栅-过渡金属硫化物单层组合结构,可大幅提升过渡金属硫化物单层光致发光效率.利用Purcell效应对自发辐射速率进行控制,得到峰值为3.4倍的发光增强.研究了单层二硫化钨以及单层二硒化钨在设计结构上的光致发光信号,通过实验证实了过渡金属硫化物单层与亚波长光栅耦合结构中光致发光增强的可行性,为二维材料在光电器件中的应用提供了一个新思路.     

二维半导体微纳光腔中光与物质的耦合

二维半导体具有独特的二维材料属性、新奇的谷电子能带结构和丰富的调控自由度,为凝聚态物理、光学等领域的研究带来了机遇。然而,这些研究依然存在许多根本问题,例如光的利用效率低、量子特性易受环境扰动等。将二维半导体和精密微纳光腔进行耦合不仅为这些问题的解决提供了合适的方案,还展现了前所未有的新颖光学效应,从而为二维半导体的基础物理研究和光电应用开拓了新的研究方向。对近10年来微纳光腔中二维半导体中的光与物质耦合的研究进展进行梳理,重点讨论了二维半导体的光学特性,以及二维半导体与微纳光腔的不同耦合区域的研究进展、调控机制及其在纳米激光光源、谷电子学、量子光学等方面的潜在应用,并对未来的发展方向和机遇进行展望。     

太赫兹量子阱光电探测器光栅耦合的模拟与优化

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     

Graphene-based heterojunction for enhanced photodetectors

Graphene has high light transmittance of 97.7% and ultrafast carrier mobility, which means it has attracted widespread attention in two-dimensional materials. However, the optical absorptivity of single-layer graphene is only 2.3%, and the corresponding photoresponsivity is difficult to produce at normal light irradiation. And the low on—off ratio resulting from the zero bandgap makes it unsuitable for many electronic devices, hindering potential development. The graphene-based heterojunction composed of graphene and other materials has outstanding optical and electrical properties, which can mutually modify the defects of both the graphene and material making it then suitable for optoelectronic devices. In this review, the advantages of graphene-based heterojunctions in the enhancement of the performance of photodetectors are reviewed. Firstly, we focus on the photocurrent generation mechanism of a graphene-based heterojunction photodetector, especially photovoltaic, photoconduction and photogating effects. Secondly, the classification of graphene-based heterojunctions in different directions is summarized. Meanwhile, the latest research progress of graphene-transition metal dichalcogenide (TMD) heterojunction photodetectors with excellent performance in graphene-based heterostructures is introduced. Finally, the difficulties faced by the existing technologies of graphene-based photodetectors are discussed, and further prospects are proposed.     

石墨烯-硅基混合光子集成电路

近年来硅基光子学已经慢慢走向成熟,它被认为是未来取代电子集成电路,实现下一代更高性能的光子集成电路的关键技术.这得益于硅基光子器件与现代的互补金属氧化物半导体工艺相兼容,能够实现廉价的大规模集成.然而,由于受硅材料本身的光电特性所限,在硅基平台上实现高性能的有源器件仍然存在着巨大挑战.石墨烯-硅基混合光子集成电路的发展为解决这一问题提供了可行的方案.这得益于石墨烯作为一种兼具高载流子迁移率、高电光系数和宽带吸收等优点的二维光电材料,能够方便地与现有硅基器件相集成,并充分发挥自身的光电性能优势.本文结合我们课题组在该领域研究的一些最新成果,介绍了国际上在石墨烯-硅基混合光子集成电路上的一些重要研究进展,涵盖了光源、光波导、光调制器和光探测器四个重要组成部分.     

Photodetectors based on junctions of two-dimensional transition metal dichalcogenides

Transition metal dichalcogenides(TMDCs) have gained considerable attention because of their novel properties and great potential applications. The flakes of TMDCs not only have great light absorption from visible to near infrared, but also can be stacked together regardless of lattice mismatch like other two-dimensional(2D) materials. Along with the studies on intrinsic properties of TMDCs, the junctions based on TMDCs become more and more important in applications of photodetection. The junctions have shown many exciting possibilities to fully combine the advantages of TMDCs, other2 D materials, conventional and organic semiconductors together. Early studies have greatly enriched the application of TMDCs in photodetection. In this review, we investigate the efforts in photodetectors based on the junctions of TMDCs and analyze the properties of those photodetectors. Homojunctions based on TMDCs can be made by surface chemical doping,elemental doping and electrostatic gating. Heterojunction formed between TMDCs/2D materials, TMDCs/conventional semiconductors and TMDCs/organic semiconductor also deserve more attentions. We also compare the advantages and disadvantages of different junctions, and then give the prospects for the development of junctions based on TMDCs.     

Band gap engineering of atomically thin two-dimensional semiconductors

Atomically thin two-dimensional(2D) layered materials have potential applications in nanoelectronics, nanophotonics, and integrated optoelectronics. Band gap engineering of these 2D semiconductors is critical for their broad applications in high-performance integrated devices, such as broad-band photodetectors, multi-color light emitting diodes(LEDs), and high-efficiency photovoltaic devices. In this review, we will summarize the recent progress on the controlled growth of composition modulated atomically thin 2D semiconductor alloys with band gaps tuned in a wide range, as well as their induced applications in broadly tunable optoelectronic components. The band gap engineered 2D semiconductors could open up an exciting opportunity for probing their fundamental physical properties in 2D systems and may find diverse applications in functional electronic/optoelectronic devices.     

拓扑量子材料光电探测器研究进展

物质拓扑态的发现是近年来凝聚态物理和材料科学的重大突破。由于存在不同于常规半导体的特殊拓扑量子态(如狄拉克费米子、外尔费米子、马约拉纳费米子等),拓扑量子材料通常能表现出一些新颖的物理特性(如量子反常霍尔效应、三维量子霍尔效应、零带隙的拓扑态、超高的载流子迁移率等),因而在低能耗电子器件和宽光谱光电探测器件领域具有重要的研究价值。本文综述了拓扑量子材料的特性与制备方法以及在光电探测领域的发展现状,重点讨论了拓扑绝缘体与拓扑半金属宽光谱光电探测器的器件结构与性能,同时也对拓扑量子材料在光电探测器领域的发展前景进行了展望。     

Photodetectors based on two-dimensional materials and organic thin-film heterojunctions

High-performance photodetectors are expected to open up revolutionary opportunities in many application fields, such as environment monitoring, military, optical communication and biomedical science. Combining two-dimensional materials(which have tunable optical absorption and high carrier mobility) with organic materials(which are abundant with low cost, high flexibility and large-area scalability) to form thin-film heterojunctions, high-responsivity photodetectors could be predicted with fast response speed in a wide spectra region.In this review, we give a comprehensive summary of photodetectors based on two-dimensional materials and organic thin-film heterojunctions, which includes hybrid assisted enhanced devices, single-layer enhanced devices, vertical heterojunction devices and tunable vertical heterojunction devices. We also give a systematic classification and perspectives on the future development of these types of photodetectors.     

Recent progress in all-inorganic metal halide nanostructured perovskites: Materials design,optical properties,and application

Low-dimensional all-inorganic metal halide perovskite (AIMHP) materials, as a new class of nanomaterials, hold great promise for various optoelectronic devices. In the past few years, tremendous progress has been achieved in the development of efficient and stable AIMHP nanomaterials for optical property studies and related applications. Here, we offer a critical overview on the unique merits and the state-of-the-art design of AIMHP using different composition strategies. Then, the effects of material compositions, dimensionality, morphologies and structures on optical properties are summarized. We also comprehensively present recent advances in the development AIMHP nanomaterials for practical applications including solar cells, light-emitting diodes, lasers and photodetectors. Lastly, the critical challenges and future opportunities in this emerging field are highlighted.     

The rise of two-dimensional tellurium for next-generation electronics and optoelectronics

Single-element two-dimensional (2D) tellurium (Te) which possesses an unusual quasi-one-dimensional atomic chain structure is a new member in 2D materials family. 2D Te possesses high carrier mobility, wide tunable bandgap, strong light-matter interaction, better environmental stability, and strong anisotropy, making Te exhibit tremendous application potential in next-generation electronic and optoelectronic devices. However, as an emerging 2D material, the research on fundamental property and device application of Te is still in its infancy. Hence, this review summarizes the most recent research progresses about the new star 2D Te and discusses its future development direction. Firstly, the structural features, basic physical properties, and various preparation methods of 2D Te are systemically introduced. Then, we emphatically summarize the booming development of 2D Te-based electronic and optoelectronic devices including field effect transistors, photodetectors and van der Waals heterostructure photodiodes. Finally, the future challenges, opportunities, and development directions of 2D Te-based electronic and optoelectronic devices are prospected.     

Photodetectors based on inorganic halide perovskites:Materials and devices

The newly emerging metal halide perovskites have attracted considerable attention due to their exceptional optoelectronic properties. This upsurge was initially driven when the power conversion efficiency of perovskite-based photovoltaic devices exceeded 23%. Due to their optoelectronic properties, perovskite materials have also been used in light-emitting diodes, photodetectors, lasers, and memory devices. This study comprehensively discusses the recent progress of allinorganic perovskite-based photodetectors, focusing on their structures, morphologies of their constituent materials, and diverse device architectures that improve the performance metrics of these photodetectors. A brief outlook, highlighting the main existing problems, possible solutions to these problems, and future development directions, is also provided herein.     

Environmental engineering of transition metal dichalcogenide optoelectronics

The explosion of interest in two-dimensional van der Waals materials has been in many ways driven by their layered geometry. This feature makes possible numerous avenues for assembling and manipulating the optical and electronic properties of these materials. In the specific case of monolayer transition metal dichalcogenide semiconductors, the direct band gap combined with the flexibility for manipulation of layers has made this class of materials promising for optoelectronics. Here, we review the properties of these layered materials and the various means of engineering these properties for optoelectronics. We summarize approaches for control that modify their structural and chemical environment, and we give particular detail on the integration of these materials into engineered optical fields to control their optical characteristics. This combination of controllability from their layered surface structure and photonic environment provide an expansive landscape for novel optoelectronic phenomena.