CAREER: Semiconductor Lasers for Generating High Energy Ultrashort (sub-50 fs) Optical Pulses: From Nanotechnology to Ultrafast Optics

rana: NSF CAREER奖的研究旨在开发全新的技术，使半导体激光器能够产生超短光脉冲。提出的研究目标是开发半导体模型锁定激光器，该激光器可以产生短于50秒的稳定光脉冲，脉冲能量大于100 pJs。这些目标将通过综合纳米技术、超快光学、材料科学和器件物理学的思想来实现，例如：a)量子点增益介质可以同时实现宽增益带宽、零啁啾和零群速度色散；b)基于纳米结构的子带间跃迁的超快器件，可以产生具有高脉冲能量的稳定超短脉冲；c)利用半导体纳米结构中人工产生的Kerr非线性的类孤子脉冲整形机制。此外，将从理论和实验两方面探讨半导体激光器中超短脉冲产生的基本方面，包括与脉冲稳定性和噪声有关的问题，半导体纳米结构中的超快载流子动力学，以及低于100 fs的脉冲成形机制，其中脉冲宽度与半导体中的载流子带内弛豫时间具有相同的顺序。电泵浦半导体激光源结构紧凑，能产生高能量稳定的超短脉冲，而且成本比固态激光器低100倍，这一成功的演示将对许多不同领域产生重大影响，包括纳米技术和材料研究、生物医学研究、医疗保健和医学研究、化学和反应动力学、检测、传感、诊断、成像和光通信系统。该职业规划将对康奈尔大学电气工程系的课程设置产生影响，这些课程将综合电气工程、半导体光电子学、超快光学、纳米技术和器件物理学等本科和研究生层次的各种观点。此外，还将举办面向高中生的暑期研习班和面向初中生的讲座和示范。将启动一项计划，通过动手实验，提高当地印第安人学校中学生对科学的兴趣。

0348501RanaThe research proposed here for the NSF CAREER award endeavors to develop radically new technologies that will enable semiconductor lasers to generate ultrashort optical pulses. The goals of the proposed research are to develop semiconductor modelocked lasers that can produce stable optical pulses shorter than 50 fs with pulse energies larger than 100 pJs. These goals will be accomplished through a synthesis of ideas from nanotechnology, ultrafast optics, material science, and device physics, such as a) quantum dot gain mediums to achieve wide gain bandwidth, zero chirp, and zero group velocity dispersion all at the same time, b) ultrafast devices based on intersubband transitions in nanostructures for generating stable ultrashort pulses with high pulse energies, and c) soliton-like pulse shaping mechanisms using artificially created Kerr nonlinearities in semiconductor nanostructures. In addition, fundamental aspects of ultrashort pulse generation in semiconductor lasers will be explored both theoretically and experimentally including issues related to pulse stability and noise, ultrafast carrier dynamics in semiconductor nanostructures, and pulse shaping mechanisms in the sub-100 fs regime where pulse widths are of the same order as the carrier intraband relaxation times in semiconductors. A successful demonstration of electrically pumped semiconductor laser sources that are compact, produce high energy stable ultrashort pulses, and cost 100 times less than solid state lasers will have a significant impact in many different areas including nanotechnology and materials research, biomedical research, healthcare and medical research, chemical and reaction kinetics, detection, sensing, diagnostics, imaging, and optical communication systems. The impact on education of the proposed career plan will be in the development of course curricula for the Electrical Engineering Department at Cornell University that will synthesize various perspectives of electrical engineering, semiconductor optoelectronics, ultrafast optics, nanotechnology, and device physics at the undergraduate and graduate levels. In addition, summer workshops for high school students and lectures and demonstrations for middle school students will be organized. A program will be initiated to promote interest in sciences among middle school students from a local native Indian school through hands on experiments.