Optical: Ultrafast all-optical switches, modulators, and wavelength converters based on intersubband transitions for Tb/s operation

当数据速率超过100 GB/S时，希望完全在光域中执行脉冲处理功能。这项研究的目的是开发超快全光开关、调制器、波长转换器和用于全光脉冲重定时、整形和再放大(3R产生)的器件，能够利用半导体量子阱中的子带间跃迁来实现接近1TB/S的速度。半导体量子阱中电子的子带间弛豫时间约为1ps。这种短的弛豫时间允许实现超快光学器件。本文提出的研究将利用GaN/AlGaN/AlN多量子阱开发工作在1.55 mm的全光信号处理器件。这里提出的器件提供了接近1 TB/S的潜在开关速度，并且需要低至100fJ的脉冲能量。将探索在子带间可饱和吸收体内通过交叉损耗调制(XLM)实现全光开关、调制和波长转换，以及在子带间光放大器中通过差分交叉相位调制(XPM)实现全光3R产生。拟议的研究涵盖了器件设计、材料生长、器件制造和器件表征的方方面面。这项研究中提出的器件的成功演示将为运行在1.55毫米处的超快光电子器件创建一个新的技术平台。这项研究将有助于发展其他工作在1.55 mm的超快子带间光电器件，如激光器、探测器、电吸收调制器和用于锁模激光器的快速可饱和吸收器。参与该项目的研究生和本科生将接受尖端光电子学方面的培训。此外，这项工作的更广泛影响将是在课程课程的开发中，这些课程将综合本科生和研究生水平的电气工程、量子工程、光学和固体物理的各种观点。

0334986RanaAt data rates exceeding 100 Gb/s it is desirable to perform pulse processing functions entirely in the optical domain. The research proposed here aims to develop ultrafast all-optical switches, modulators, wavelength converters, and devices for all-optical pulse retiming, reshaping, and reamplification (3R generation) capable of performing at speeds close to 1 Tb/s by using intersubband transitions in semiconductor quantum wells. Intersubband relaxation times of electrons in semiconductor quantum wells are around 1 ps. Such short relaxation times allow for the realization of ultrafast optical devices. The research proposed here will develop devices for all-optical signal processing operating at 1.55 mm using GaN/AlGaN/AlN multiple quantum wells. The devices proposed here offer the potential of switching speeds close to 1 Tb/s and require pulse energies as low as 100 fJ. All-optical switching, modulation, and wavelength conversion by cross-loss modulation (XLM) in intersubband saturable absorbers, and all-optical 3R generation by differential cross-phase modulation (XPM) in intersubband optical amplifiers will be explored. The proposed research covers all aspects of device design, material growth, device fabrication, and device characterization. A successful demonstration of the devices proposed in this research will create a new technology platform for ultrafast optoelectronic devices operating at 1.55 mm. The proposed research will contribute to the development of other ultrafast intersubband optoelectronic devices operating at 1.55 mm, such as lasers, detectors, electro-absorption modulators, and fast saturable absorbers for modelocked lasers. Graduate and undergraduate students involved in this project will get training in cutting edge optoelectronics. In addition, the broader impact of this work will be in the development of course curricula that will synthesize various perspectives of electrical engineering, quantum engineering, optics, and solid state physics at the undergraduate and graduate levels.