Artificial Atoms: Quantum Optics and Spin Physics of Quantum Dots

Who: Edward (Ned) Flagg, West Virginia University
When: 
Thursday, October 3, 2019 - 4:00pm
Where: 
321 Allen Hall

Semiconductor quantum dots (QDs) are nanoscopic crystals that are often called artificial atoms. Charge carriers trapped within them have discrete energy levels in the fashion of single atoms, and they absorb and emit light at discrete wavelengths corresponding to those energy levels. Because of this, in many ways QDs behave like the canonical two-level quantum system, which makes them suitable for experiments involving the quantum nature of light, which is called quantum optics. For this reason and for their potential uses in quantum information applications, QDs attract great scientific interest.
 
I will describe how QDs demonstrate quantum optical behaviors exhibited by single atoms, showing that they really do act like artificial atoms. Then I'll discuss ways in which the solid-state environment of the QDs complicates the situation in ways that single atoms do not experience. Finally, I'll present some recent work in controlling the spin of an electron trapped in a QD with the aim of using it as a quantum bit.