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

0348501RanaNSF CAREER奖的研究计划致力于开发全新的技术，使半导体激光器能够产生超短光脉冲。拟议研究的目标是开发半导体锁模激光器，可以产生稳定的光脉冲短于50 fs，脉冲能量大于100 pJ。这些目标将通过纳米技术、超快光学、材料科学和器件物理学的综合思想来实现，例如a）量子点增益介质，以同时实现宽增益带宽、零啁啾和零群速度色散，B）基于纳米结构中的子带间跃迁的超快器件，用于产生具有高脉冲能量的稳定超短脉冲，以及c）在半导体纳米结构中使用人工产生的克尔非线性的类孤子脉冲整形机制。此外，在半导体激光器中超短脉冲产生的基本方面将在理论和实验上进行探索，包括与脉冲稳定性和噪声，半导体纳米结构中的超快载流子动力学，以及脉冲整形机制有关的问题，其中脉冲宽度与半导体中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是紧凑的，产生高能量稳定的超短脉冲，成本比固态激光器低100倍的成功演示将在许多不同的领域产生重大影响，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。拟议的职业计划对教育的影响将是在康奈尔大学电气工程系课程的发展，将综合电气工程，半导体光电子，超快光学，纳米技术和设备物理学的各种观点在本科和研究生水平。此外，还将为高中生举办暑期讲习班，为中学生举办讲座和示范。将启动一个方案，通过动手实验，促进当地印第安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.