Intersubband All-Optical Switching and Optically-Pumped Light Emission with III-Nitride Quantum Wells

子带间全光开关和光抽运的III-氮化物量子阱0622102DRRoberto Paiella波士顿大学的智慧优点：半导体量子结构中的子带间跃迁为器件应用提供了几个显著的特征，例如极大的设计灵活性、超快的弛豫寿命和大的光学非线性。到目前为止，它们主要用于中红外和远红外光电子器件；然而，它们的基本特性也非常适合于光纤通信波长的超高速非线性光交换--这是未来全光网络的关键组成部分，目前还没有足够的器件技术。GaN/AlGaN量子阱是一种具有足够大的导带偏移量用于近红外子带间跃迁的材料体系。研究人员提出了几种基于III-氮化物子带间系统的新型全光开关技术，包括利用耦合量子阱和库仑效应进行交叉吸收调制，基于光克尔效应的偏振开关，存在光泵浦的交叉增益调制，以及拉曼散射波长转换。该项目将重点研究这些器件的设计、材料开发和演示；还将研究基于同一平台的光泵浦发射器和激光器，作为发展近红外量子级联激光器的关键一步。更广泛的影响：拟议的全光交换机通过支持超宽带通信网络的发展，有可能在信息技术领域产生革命性的影响。此外，该项目将通过对学生进行各种学科的培训来促进教育，从外延生长到量子工程，到超快和非线性光学，再到光通信。拟议的教育活动包括：(I)为器件工程师开发一门量子力学本科课程；(Ii)开发一门关于半导体量子结构和光子器件的研究生课程；(Iii)创建一个关于先进GaN基器件的期刊俱乐部和相关网站；以及(Iv)让学生--包括本科生和高中实习生--参与并指导拟议的研究。这笔补助金还将为一名女性博士生提供工资支持。最后，这项工作将促进对氮化物异质结构材料和器件的广泛领域的总体认识。

Intersubband All-Optical Switching and Optically- Pumped Light Emission with III-Nitride Quantum Wells 0622102Dr. Roberto PaiellaBoston UniversityIntellectual merit: Intersubband transitions in semiconductor quantum structures offer several remarkable features for device applications, such as great design flexibility, ultrafast relaxation lifetimes, and large optical nonlinearities. So far they have been primarily employed in mid- and far-infrared optoelectronic devices; however, their basic features are also ideally suited to ultrafast nonlinear optical switching at fiber-optic-communications wavelengths - a key ingredient of future all-optical networking for which no adequate device technology yet exists. A promising material system with large enough conduction-band offsets for near-infrared intersubband transitions is that of GaN/AlGaN quantum wells. The investigators have proposed several novel all-optical-switching techniques based on III-nitride intersubband systems, including the use of coupled quantum wells and Coulomb effects for cross-absorption modulation, polarization switching based on the optical Kerr effect, cross-gain modulation in the presence of optical pumping, and wavelength conversion by Raman scattering. This project will focus on the design, material development, and demonstration of these devices; optically pumped emitters and lasers based on the same platform will also be investigated, as a key step towards the development of near-infrared quantum cascade lasers. Broader impacts: The proposed all-optical switches have the potential for a revolutionary impact in the field of information technology, by enabling the development of ultra-broadband communication networks. Furthermore this project will promote education through the training of students in a variety of disciplines, ranging from epitaxial growth, to quantum engineering, to ultrafast and nonlinear optics, to optical communications. Proposed educational activities include (I) the development of an undergraduate course on quantum mechanics for device engineers, (II) the development of a graduate course on semiconductor quantum structures and photonic devices, (III) the creation of a journal club and associated website on advanced GaN-based devices, and (IV) the engagement and mentoring of students - including undergraduates and high-school interns - in the proposed research. This grant will also provide salary support for a female Ph.D. candidate. Finally, this work will advance the general state of knowledge in the broad area of nitride heterostructure materials and devices.