Optical Physics, Quantum Electronics, and Photonics

Many dramatic developments in science and technology have resulted from applications of the laser both to the fields of telecommunications, materials processing, and remote sensing and as a diagnostic tool in biology, chemistry, and physics. A number of Applied Physics faculty members have made major contributions to these laser-related areas. 

One such area is in the development and use of lasers that produce sub-100 femtosecond pulses (a femtosecond = 10-15 second). New or improved sources of ultrashort pulses are under development, including diode-pumped all-solid-state systems and compact fiber-based sources. Femtosecond sources have been used to monitor the course of chemical reactions, to observe molecular dynamics with femtosecond resolution, and to study carrier dynamics in semiconductors and for ultra-high-speed optoelectronics. Nonlinear propagation effects with femtosecond pulses are also the subject of extensive research, including the generation of spatio-temporal solitons (i.e., pulses propagated without diffracting in space or dispersing in time) and the nonlinear dynamics associated with catastrophic pulse collapse due to self-focusing. 

Considerable efforts at Cornell are devoted to the photonics area, particularly with potential applications to telecommunications. These research topics include photonics crystal structures that could allow for the development of optical "circuits" and of novel types of optical fiber that have unique capabilities not possible with current telecommunications fiber designs. Semiconductor quantum "dots" are being investigated for potential development of highly broadband optical amplifiers and nonlinear optical switches. The goal of this research is to increase the bandwidth of telecommunications systems and to develop "all-optical" systems that minimize electronic components. 

Applied Physics faculty members are engaged in a number of other optics-related efforts. These include the development of new and improved optoelectronic devices using compound semiconductor heterostructures; projects concerned with the identification, production, and application of new nonlinear optical materials; and research on sensors for chemical sensing and biological applications.