Quantum Dot Laser Diodes and Mode-Locking

Speaker:  Dr. Luke. F. Lester, Professor and ECE Department Head

Host: MICS

Date: September 5 (Friday), 2014
Time: 3:00 PM - 4:00 PM
Location: Whittemore 654 (6th Floor Conference Room)

Abstract:

The unique advantages of quantum dot (QD) materials, such as ultra broad bandwidth, ultra fast gain dynamics, low linewidth enhancement factor and easily saturated gain and absorption, make them a desirable choice for semiconductor monolithic mode-locked lasers (MLLs). This talk will discuss the modeling and characterization of quantum dot MLLs and identify what differentiates them from other semiconductor lasers in terms of temperature performance and pulse stability. Reconfigurable devices will also be presented that are capable of repetition rates from 2-100 GHz. These multi-section QD MLLs are beneficial for diverse waveform generation since they can demonstrate higher order harmonics of a laser’s fundamental repetition rate simply by placing the saturable absorber section at different locations within the laser cavity. The small size, low power consumption, and direct electrical pumping of quantum dot monolithic MLLs make them promising candidates for optical clock distribution, high bit-rate optical time division multiplexing, and compact microwave generation.

Speaker:

Luke F. Lester, who is an IEEE and SPIE Fellow, received the B.S. in Engineering Physics in 1984 and the Ph.D. in Electrical Engineering in 1992, both from Cornell University. Prior to joining Virginia Tech in August 2013, he was a professor of ECE at the University of New Mexico (UNM) for 19 years, and, most recently, the Interim Department Chair and the Endowed Chair Professor in Microelectronics there. From 1985-1994, Dr. Lester worked as an engineer for the General Electric Electronics Laboratory in Syracuse, New York where he worked on transistors for mm-wave applications. There in 1986 he co-invented the first Pseudomorphic HEMT, a device that was later highlighted in the Guinness Book of World Records as the fastest transistor. In 2001, he was a co-Founder and Chief Technology Officer of Zia Laser, Inc., a startup company using quantum dot laser technology to develop products for communications and computer/microprocessor applications. The company was later acquired by Innolume, GmbH. Dr. Lester’s awards and honors include: a 1986 IEE Electronics Letters Premium Award for the first transistor amplifier at 94 GHz; the Best Paper Award at SPIE’s Photonics West 2000 for reporting a quantum dot laser with the lowest semiconductor laser threshold; and the 2012 Harold E. Edgerton Award of the SPIE for his pioneering work on ultrafast quantum dot mode-locked lasers. He has published at least 136 journal articles and over 250 conference papers.