CMT Seminar: Michael Gullans

Title: Quantum Optics in Low-dimensional Electron Systems: Cavity-Coupled Double Quantum Dots and Quantum Hall Devices

Abstract: The electronic and optical properties of semiconductor systems are dramatically affected by reduced dimensionality. Two well-known exa-mples (with origins in the study of field effect transistors) are the formation of gate-defined quantum dots (DQD) and the quantum Hall effect.  In this talk, I will describe our recent work studying quantum optical effects in these two systems.  First, I will describe the non-classical states of light that emerge when a cavity-coupled DQD is periodically driven in the regime photon-assisted tunneling.  Depending on drive parameters, we find different regimes where the system achieves single-photon emission, lasing without inversion, and thermalization of light with a chemical potential.  I will then describe the optical response of quantum Hall states in Dirac materials when the carrier mean-free path exceeds the resonant wavelength for the inter-band Landau level transitions.  In this regi-me, we find that the scattered light from the bulk can be used to image the disorder landscape, while the edge states can be used to generate coherent light with high orbital angular momentum.