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.     

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。     

液晶人工神经元阵列的研制

研制了一种液晶灵巧像素光学神经元阵列器件，它利用光电混合集成技术，以非晶硅作光敏材料，以液晶实现光调制，通过特殊设计的器件结构，能实现对两束光的相减和非线性取阈等人工神经元功能。该器件具有８×８个神经元，以全并行方式工作     

硅基混合表面等离子体纳米光波导及集成器件

总结并展望了硅基混合表面等离子体纳米光波导及集成器件方面的理论和实验研究工作。首先介绍了几种硅基混合表面等离子体纳米光波导结构,其尺寸可小至100 nm以下,而传播长度达100μm量级;其次介绍了基于硅基混合表面等离子体纳米光波导的功分器、偏振分束器和谐振器等集成器件,其尺寸为亚微米量级;最后探讨了硅基混合表面等离子体纳米光波导与硅纳米线光波导的耦合及对其进行增益补偿。     

光纤到户用光电集成单纤双向器件的研究

研究了光电集成器件的耦合与封装的关键技术,首先分析光纤与PLC波导的z向偏移及角度偏移与耦合效率的关系,发布其3dB容差分别为70μm及5°以内,并分析存在8°反射角及填充折射率匹配胶时耦合情况并仿真验证。该器件采用表面贴光子技术、无源对准、非气密封装实现光与电、有无源的多功能结合。测试了器件的激光器与探测器性能,测试结果表明,该光电集成器件边模抑制比、灵敏度等参量优良。     

PdSe2纳米线薄膜/Si异质结近红外集成光电探测器

提出了一种PdSe2纳米线(NWs)薄膜/Si异质结近红外集成光电探测器.采用热辅助硒化预先制备Pd NWs的方法合成大面积PdSe2 NWs,通过组装和转移NWs可制备包含8×8器件单元的集成光电探测器.光电性能测试结果表明,所设计的器件在200～1300 nm宽波段范围内均有明显的光响应,峰值位于810 nm附近.在零偏压下,器件在810 nm处的响应度(R)为166mA·W-1,当施加-2V偏压时,R值显著提高至3.24 A·W-1.此外,集成器件呈现出优异的均匀性,64个器件的电流开关比均为60左右.由于良好的性能均匀性,该集成光电探测器可应用于图像传感领域,能可靠地记录近红外光投射的"LASDOP"字母图像,展示了潜在的应用前景.     

第一讲光电子器件在光纤通信中的应用

光纤通信技术发展的阶段性飞跃总是伴随新型光电材料和功能器件的突破．文章介绍了光纤通信系统中应用到的各种光电子器件，从光纤通信的3个环节：光发送、光接受、光放大为出发点，着重阐述了半导体激光器、光调制器、光检测器、光放大器等关键器件的基本原理、工作特性以及发展现状和趋势，并在回顾传统集成光电子器件发展的同时，展望了以新一代微纳结构光电子器件为基础的光子集成技术的发展趋势。     

10Gb/s带可变光衰减器的雪崩光电二极管接收器(英文)

报导了一种集成MEMS的光接收器件的10Gb/s雪崩光电二极管,并介绍了10Gb/s APD-TIA的结构和基本特点.对衰减器进行了性能测试,所得到的特性曲线表明其衰减随所加电压变化而变化.集成MEMS VOA接收器的动态范围至少增加了50%达到13dB,这个结果对密集波分复用系统中的应用非常理想,同时对高速通信系统中的信号改变是一种有效的补偿方式.本文报导了传输速率10Gb/s带衰减器的雪崩光电二极管光接收器的眼图和测试结果,能够获得的灵敏度和清晰的眼图雪崩光电二极管光接收器的眼图和测试结果,能够获得-26.5dBm的灵敏度和清晰的眼图.     

多孔硅的光生伏特效应

多孔硅(PS)的可见光致发光的发现[1],引起人们对PS的光电特性及其在光电器件上应用可能性的广泛探索.已报道用PS制成发出可见光的电致发光器件[2]及高灵敏的光探测器件[3].本文将报道PS层与金属接触,光照时能出现很强的光生伏特效应,利用这一特性有可能制成高效的光电转换器件.     

实时光电混合联合变换相关器单元的实验研究

本文根据联合变换相关的原理，提出了一种实时光电混合联合变换相关器，它采用一个液晶光阀作为输入器件，用另一个液晶光阀记录和显示联合功率谱，所给出的实验结果证实了该系统设计及性能分析的正确性。     

Voltage-controllable wavelength-selective optical switching based on multiply cascaded long-period fiber gratings

A novel wavelength-selective optical switching device based on multiply cascaded long-period fiber gratings is proposed and experimentally demonstrated. The on and off states of each channel in the optical switching device can be effectively switched by voltage-controllable coil heaters. The device has advantages of multichannel operation, multiwavelength selectivity, and bandwidth controllability. It can be useful for applications in multiwavelength operational signal gating, optical switching devices, routers, and multiplexers in optical communication systems.     

Computations for the design of an integrated surface acoustic wave controlled semiconductor optical source

A superluminescent diode monolithically integrated with a surface acoustic wave Bragg-cell to operate as a beam deflector is proposed. The analysis procedures for determining the acoustic and optical modes, and modal diffraction of the optical beam are employed to develop a practical model for the integrated device. Results from this model are used to assess the operational characteristics of the proposed integrated device and to provide design guidelines.     

场效应晶体管—自电光效应器件灵巧像素的实验研究

在一块印刷电路板上通过将自电效应器件（ＳＥＥＤ）与ＧａＡｓ场效应晶体管（ＦＥＴ）进行互连制作一种简单的场效应晶体管－自电光效应器件（ＦＥＴ－ＳＥＥＤ）灵巧像素，这种灵巧像素由一个输入自电光效应器件，一个输出自电光效应器件及一个ＧａＡｓ场效应晶体管放大器构成，设计了一个光学系统，在这个系统以对这种灵巧像素进行了演示及测试，并对其工作原理及过程进行了描述。     

A laser speckle pattern technique for designing an optical computer mouse

A laser speckle pattern (LSP) technique for designing an optical computer mouse is presented. The LSP is used to determine the velocity of the device in a way that allows working on a wide class of surfaces. The operational principles of the laser speckle pattern technique are explained. The results of computer simulation tests, carried out for proving its ability to work and the efficiency of the device, are given.     

Status of PRESS-MAG-O: The experimental apparatus to probe materials and phenomena under extreme conditions at Frascati

In this contribution we up-to-date the status of the PRESS-MAG-O device, a new instrument under commissioning at the INFN designed to perform magnetic and spectroscopic experiments on samples under extreme conditions. The system has been designed to work at SINBAD, the IR synchrotron radiation beamline operational at DAΦNE. The instrument, that is the result of a significant R&D, will allow performing concurrent high harmonic ac magnetic susceptibility measurements and magneto-optic experiments on a sample under high pressure, with a variable DC magnetic field in a wide temperature range. The vacuum vessel has been designed with four crossing windows to allow optical measurements in the transmission geometry on the sample loaded inside a Diamond Anvil Cell. A new superconducting miniaturized micro-SQUID gradiometer has been also developed to detect the low magnetic signal of the sample and a customized optical system has also been designed to perform IR synchrotron radiation experiments.     

Polarization-selective switching in holographically formed polymer dispersed liquid crystals

We have developed an optical stack of holographically formed polymer dispersed liquid-crystal (H-PDLC) devices that is fully operational with nonpolarized light sources. The device consists of two H-PDLC transmission gratings separated by a passive polarization rotator that can output a diffracted s-polarized, p-polarized, or s- and p-polarized beam simultaneously.     

A bistable liquid crystal electro-optic modulator

A new liquid crystal hybrid bistable optical device is described. Optical bistability has been observed and the use of this device for optical logic elements and ultralinear modulation applications demonstrated. The transient response of the device for optical logic elements and ultralinear modulation applications demonstrated. The transient response of the device has also been studied and a “critical slowing down” phenomenon observed.     

微环谐振器

光学微环谐振器自从1969年作为滤波器件被提出以后,就受到了很大的关注。光学微环谐振器,可以作为一种通用设备用于实现通信与信号处理中的所有一般功能,比如滤波、复用／解复用、调制、开关、延时、门电路、路由、传感和放大等。小尺寸的微环有优异的特性：宽带宽、高精细度。这些特性非常有利于非线性光学应用。高的精细度意味着环中高的储存能量,而且可以通过进一步减小模场面积再次提高,并且不牺牲带宽。因为利用平面工艺易于获得微环,所以其非常适合大规模集成。简单介绍了微腔的概念,具体介绍了微环谐振器,以及马里兰大学的一些主要工作,最后分析了这种技术的挑战和发展前景。     

Effect of optical radiation in a photo-DOVATT

Avalanche photodetectors are very important solid-state detectors currently used in long-distance and wide-band optical communication systems, due to their faster speed of response compared to other solid-state photodiodes. Furthermore, it has been found that by using heterostructures one can improve both multiplication gain and quantum efficiency of such a device. DOVATT is a heterojunction impatt device in which there is one avalanche zone followed by two drift zones at different scattering limited velocities. The device is very useful for generation of high power in the X-band.The present paper examines the effect of optical radiation on such a device. Studies have been made on the frequency-response characteristics of the device. The results show that the device has the potentiality of becoming a powerful photodetector in optical communication systems.     

Table-top KrF amplifier delivering 270 fs output pulses with over 9 W average power at 300 Hz

Applying the combination of a solid-state Ti:Sa laser system and a newly developed wide-aperture, discharge-pumped KrF amplifier, output pulses with over 9 W average power at 300 Hz have been achieved in a single output beam. The frequency-tripled seed pulses of the Ti:Sa system – delivering approximately 10 μJ energy at 248 nm – were amplified to over 30 mJ using a 3-pass off-axis amplification scheme. The optical set-up has been fitted to the amplifier’s parameters, and stored-energy measurements were carried out with different parameters in order to optimize the operational conditions of the device for the highest average power. Received: 10 June 2002 / Published online: 25 September 2002 RID="*" ID="*"Corresponding author. Fax: +49-551/503-599, E-mail: jbekesi@llg.gwdg.de