Semiconductor Physics and Photonics

这项研究集中在Riber 32P分子束外延机上生长的半导体异质结构，该设备专门用于非线性光学，可能是世界上唯一的一台。在过去的几年里，在理解半导体的带边非线性以及设计、制造和操作非线性光学器件方面，人们已经获得和发展了大量的实验和理论能力和经验。在同一屋檐下拥有设计、生长、制造、线性和非线性光谱以及多体理论的能力，加速了这一过程，导致了协同作用。在非线性材料方面，将重点研究应变层超晶格的能带结构、光学非线性和增益，作为低功率非线性器件和低阈值激光器的材料。对波导结构的研究包括有电流注入和无电流注入的非线性定向耦合器，电流注入的多-n相移器，以及10微米的子带间跃迁激光器。对标准具结构的研究主要集中在用于光通信的全光开关、低功率慢响应标准具以及垂直腔面发射激光器对外部反馈的敏感性等方面。非线性光学的所有发现都同样适用于光电子学，因为半导体的稳态室温带边特性仅由如何产生的载流子密度决定。//

This research focuses on semiconductor heterostructures grown in a Riber 32P molecular beam epitaxy machine dedicated exclusively to nonlinear optics, probably the only one in the world. Over the last several years considerable experimental and theoretical capabilities and experience have been acquired and developed to understand the band-edge nonlinearities of semiconductors and to design, fabricate, and operate nonlinear optical devices. Having under one roof capabilities for design, growth, fabrication, linear and nonlinear spectroscopy, and many-body theory has accelerated this process, leading to synergistic interactions. In the area of nonlinear materials, research will focus on the bandstructure, optical nonlinearity, and gain of strained layer superlattices, relevant as materials for low-power nonlinear devices and low-threshold lasers. Research on waveguide structures includes nonlinear directional couplers with and without current injection, as many-n phase shifter by current injection, and a 10-um intersubband-transition laser. Research on etalon structures concentrates on all- optical switches for optical communication, low- power slow-response etalons, and the sensitivity to external feedback of vertical-cavity surface- emmitting lasers. All findings for nonlinear optics apply equally well to optoelectronics, since the steady-state room-temperature band-edge properties of a semiconductor are determined solely by the carrier density however generated. //