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

基于iii -氮化物量子阱的子带间全光开关和光泵浦光发射智力优势：半导体量子结构的子带间跃迁为器件应用提供了几个显着的特性，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，它们主要应用于中、远红外光电器件；然而，它们的基本特性也非常适合光纤通信波长的超快非线性光交换，这是未来全光网络的关键组成部分，目前还没有足够的设备技术。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有前途的材料体系。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，包括使用耦合量子阱和库仑效应进行交叉吸收调制，基于光学克尔效应的偏振开关，存在光泵浦光增益调制以及拉曼散射的波长转换。该项目将侧重于这些设备的设计、材料开发和演示；基于同一平台的光泵浦发射器和激光器也将被研究，作为近红外量子级联激光器发展的关键一步。更广泛的影响：拟议的全光交换机通过实现超宽带通信网络的发展，在信息技术领域具有革命性影响的潜力。此外，该项目将通过培养各种学科的学生来促进教育，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)为设备工程师开设量子力学本科课程，（II）开发半导体量子结构和光子器件研究生课程，（III）创建基于先进gan的设备的期刊俱乐部和相关网站，以及（IV）参与和指导学生（包括本科生和高中实习生）参与拟议的研究。该基金还将为女博士候选人提供工资支持。最后，这项工作将促进氮化物异质结构材料和器件广泛领域的一般知识状态。

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.