Speaker
Description
Semiconductor quantum dots, with their capability of confining charge carriers and various spin configurations resulting from it, can be regarded as a highly versatile platform for generating non-classical
light. While the generation of single photons or entangled photon pairs from quantum dots utilizes the so- called bright excitons and biexcitons respectively, quantum dots can also host optically dark
excitons. Such states are optically inactive due to the spin-selection rules. Because of their longer coherence times, direct and coherent optical excitation and control methods of dark states are of great
interest in modern quantum information protocols. In this work we demonstrate a stimulated excitation and control of a dark exciton via the biexciton state in a GaAs/AlGaAs quantum dot in the
presence of an in plane magnetic field. The versatility of our scheme allows not only for a deterministic preparation, but storage and a temporal retrieval of the dark state population, giving rise to a
programmed single photon/photon pair emission.
