Picosecond Pulse Generation by Transverse Mode-Locking of Monolithic Vertical-Cavity Surface-Emitting Lasers

University Of Pittsburgh, Pittsburgh PA

Investigators

Abstract

Abstract ECCS-0801869 A. Heberle, University of Pittsburgh Objective: Mode-locking of lasers is an important technique for generation of frequency combs and trains of picosecond or femtosecond optical pulses. So far, only longitudinal modes have been locked reliably, leading to pulses traveling around the laser cavity in direction of to the light beam. Intellectual Merit: The goal of this experimental research program is the investigation of a new process, lateral two-dimensional mode-locking in monolithic vertical-cavity surface-emitting lasers (VCSEL?s), and the fabrication/exploration of novel devices for picoseconds or even femtosecond pulse and frequency comb generation. The project aims to demonstrate that lateral mode-locking of round VCSEL?s produces solitons that move in circles around the emission aperture. This work will not only provide understanding of ultrafast dynamics and soliton propagation in VCSEL?s, but it will add ultrafast mode-locking and frequency comb generation to this increasingly important class of lasers. It is expected, for example, that laterally mode-locked VCSEL?s will provide two orders of magnitude better control of the pulse repetition rate than conventional, longitudinally mode-locked monolithic semiconductor lasers, in which the repetition rate can be tuned by only about 0.5%. Mode-locked VCSEL?s could have significant applications for optical communication, sensing, and displays in which the blue and green colors are generated by frequency doubling. Broader Impact: The project gives graduate and undergraduate students hands-on experience in several important fields: femtosecond technology, photonics, nanoscience, and semiconductor technology. It also supports the interdisciplinary photonics course program and the early lab experience program that involves underrepresented minorities at the University of Pittsburgh