WIN Seminar Series: Tensile-strained Self-assembly of Quantum Dots for Entangled Photon Sources and Band Structure Engineering

Please join the Waterloo Institute for Nanotechnology on Thursday, May 16, 2019 for a guest lecture by Dr. Paul Simmonds from the Department of Physics, Micron School of Materials Science and Engineering and Boise State University. He will be speaking on "Tensile-strained Self-assembly of Quantum dots for Entangled Photon Sources and Band Structure Engineering".

Abstract:

Since the early 1990s, self-assembled quantum dots (QDs) have been the subject of intensive research for technologies ranging from high-stability lasers, to intermediate band solar cells. Driven by compressive strain, semiconductor QDs form spontaneously on the (001) surfaces of both III-V and group IV materials. That being said, QDs grown on non-(001) surfaces, and QDs grown under tensile rather than compressive strain, are highly desirable for certain applications. The low fine-structure splitting of (111) QDs should make them ideal entangled photon sources; tensile-strained QDs would have dramaticaly reduced semiconductor band gaps, with implications for infrared optoelectronics and nanoscale band structure engineering. However, until recently it has been enormously challenging to sythesize non-(001) or tensilestrained QDs that are free from crystallographic defects.

Bio:

Dr. Paul Simmonds completed his Ph.D. in semiconductor physics at the University of Cambridge in 2008, followed by postdoctoral positions at the University of Minnesota, UCSB, and Yale University. While at Yale, Simmonds discovered that by using tensile strain it is possible to create III-V quantum dots on (110) and (111) surfaces, with implications for the fields of quantum computing and spintronics. Starting in 2011, he managed the Integrated NanoMaterials Laboratory at UCLA, and Chaired the IEEE Photonics Society chapter. Dr. Simmonds joined Boise State University as Assistant Professor in 2014, with joint appointments in Physics and Materials Science & Engineering. He is a Senior Member of the IEEE, and a National Science Foundation CAREER awardee.