Boston Chapter of the IEEE Photonics Society

Abstract:  Light emission from silicon (Si) is an indirect (phonon-mediated) process with low probability. As a consequence, fast non-radiative recombination paths (such as trap recombination, Auger and free carrier absorption) prevent efficient photon emission and population inversion in Si. Despite of this, several strategies have been recently developed to turn Si into an efficient light emitting material. Among all the different approaches investigated so far, Si nanocrystals (Si-nc) and Si-nc rare-earth doping have shown the best results. In this talk, I will review the main achievements in the field and present our research activities aimed at engineering novel, nanostructured-based materials solutions for CMOS-compatible optically and electrically driven light sources.  

In particular, I will discuss the state of the art of the optical and electrical properties of Si-nc nucleated in Si-rich nitride (SRN) matrices and their potential for sensitized, efficient 1.55 m emitters based on energy transfer phenomena.

Biography:  Luca Dal Negro received both the Laurea in physics, summa cum laude, in 1999 and the Ph.D. degree in semiconductor physics from the University of Trento, Italy, in 2003. After his Ph.D., in 2003 he joined MIT as a post doctoral associate. Since January 2006 he is Assistant Professor in the Department of Electrical and Computer Engineering at Boston University.

He manages and conducts research projects on silicon-based photonic materials and devices and semiconductor laser spectroscopy. His main focus is currently on quantum dots spectroscopy, complex photonic crystals structures, silicon-based plasmonics and nano-photonics. He has authored and coauthored more than 50 technical articles.

Location:  MIT Lincoln Laboratory