Semiconductor Cavity QED

University Of Arizona, Tucson AZ

Investigators

Abstract

Cavity quantum electrodynamics (cQED), one of the most curious and fundamental aspects of optical physics, explores quantum dynamical processes for individual quantum objects strongly coupled to an electromagnetic resonator making two objects into one composite quantum system. One experimental bottleneck for cQED experiments using atoms is atomic motion. Atomic motion was recently reduced, but not stopped, by using lasers and magnets to cool and trap the atoms. In this project a semiconductor quantum system (quantum dot) will be coupled to a resonator. This system will explore different physics than atomic counterparts because the quantum dot does not move. Added features of the proposed experimental system are that the quantum dots will be coupled to an electromagnetic resonator constructed of a structured material called a photonic crystal. The photonic crystal resonator volume is near the minimum possible and confinement of the electromagnetic field is very high, so the coupling between the quantum dot and the electromagnetic field is very strong. Moreover, the structure is stable and totally integrated so it can be used over and over again. This research project will focus on the group's emerging capability to investigate a semiconductor nanosystem where individual quanta play a decisive role. The first specific goal of this project is to observe laser behavior from a single quantum dot. Other goals are to demonstrate a "photon blockade," which turns a incident laser beam into sequence of photons exhibiting quantum mechanical statistics, and to see the multiphoton coupling between the cavity and the quantum dot. Two graduate students will gain broad experience with semiconductor sample manipulation, nanopositioning, resolution-limited optics, continuous-wave and ultrafast-laser spectroscopy, and photon statistics measurements. The nanophotonics industry is also impacted by the education of undergraduate and graduate students trained in the basic physics and experimental skills of nanodevices. The PI of this project is the senior Faculty Associate for the College of Optical Sciences as a part of the NSF ADVANCE Institutional Transformation award to create a multi-tiered strategy for improving the representation and advancement of women in science, technology, engineering, and math fields. Cavity quantum electrodynamics with strong coupling enables nanoscience to go beyond traditional nonlinear optics and laser physics into a new regime with dynamical processes and active devices now involving quantum dots and photons taken one by one. This research will enable links between the atomic and semiconductor materials communities.