题目：Advanced quantum dot and photonic crystal technologies for integrated nano-photonic circuit

报告人：Prof. Kiyoshi Asakawa（National Institute of Materials Science (NIMS), Tsukuba, 305-0047, Japan；University of Tsukuba, Tsukuba, 305-8577, Japan）
               
摘要：
Two kinds of nano-photonic technologies, i.e., GaAs-based two dimensional photonic crystal (2DPC) slab waveguides (WGs) and InAs-based quantum dots (QDs) were developed for key photonic device structures in the future advanced telecommunication systems. For an ultra-fast digital photonic network, an ultra-small and ultra-fast symmetrical Mach–Zehnder (SMZ)-type all-optical switch (PC-SMZ) has been developed in the first stage. In the second stage, the PC-SMZ is now evolving into a new functional key device, i.e., an ultra-fast all-optical flip-flop (PC-FF) device that is essential for the digital photonic network. Through the two stages, two important techniques were developed so far. One is a new simulation method, i.e., topology optimization method of 2DPC WGs with wide/flat bandwidth, high transmittance and low reflectivity. Another is a new selective-area-growth method, i.e., metal-mask MBE method of InAs QDs. This technique contributes to achieving high-density and highly uniform InAs QDs in a desired area such as an optical nonlinearity-induced phase shift arm in the PC-FF. For a quantum information system, a single photon qubit composed of a QD ensemble, or desirably single QD, embedded in a PC-based high-Q cavity has been studied as an application of the PC/QD-combined nano-photonics. Purcell effect specific to the photon-localized system has been observed so far. As a unique site-controlled QD technique, a nano-jet probe (NJP) method has also been developed for positioning a single QD at the centre of the PC high-Q cavity. All these results will pave the way for implementation of innovative photonic devices in the advanced ultra-fast photonic network system.

Prof. Kiyoshi Asakawa简介：

Kiyoshi Asakawa分别在1968和1992年在东京大学获得学士和博士学位，1968年加入NEC中央研究所，1988年成为NEC光电技术研究所基础研究部部长，1993年成为主席研究员，1996年成为飞秒技术研究所（FESTA）统括group leader，2004年成为筑波大学TARA中心教授，2008年成为日本国家材料研究所 (NIMS)董事。其间，他还担任过美国UCSB的客员研究员（1987-1988），日本北海道大学（1998，2001）和筑波大学（1993-2002）的客员教授。Asakawa 教授的研究领域主要涉及半导体光电子学，特别是近年主要集中在半导体纳米光子学，包括半导体纳米结构、纳米加工技术和纳米器件。迄今，他已在重要的国际学术期刊 (PRL, APL, PRB和Nature Physics等) 上发表论文139篇，出版学术专著7部，国际会议上作报告200次（其中70个大会邀请报告）。此外，他还获得多个国内和国际学术奖，多次担任国际大会的组织委员。

时间：2008年5月30日（星期五）下午3：30  
   
地点：中科院物理研究所D楼211会议室

联系人：李志远  研究员（Tel：82648106）
金奎娟  研究员（Tel：82648099）

主办单位：中国科学院光物理重点实验室