<title>Toward high-efficiency regulated single-photon generation using a single quantum dot in a three-dimensional microcavity</title>

Abstract

In experiments conducted nearly 20 years ago, the spontaneous emission from single atoms was modified using electromagnetic cavities. In a condensed matter analogy to a single atom, we demonstrate that the spontaneous emission from an isolated InAs quantum dot can be modified as well. The single quantum dot spontaneous emission is coupled with high efficiency to a single, polarization-degenerate cavity mode using a compact, semiconductor resonator structure. The quantum dot is embedded in a planar epitaxial microcavity, which is processed into a post of submicron diameter. The single quantum dot spontaneous emission lifetime is reduced from the noncavity value of 1.3 ns to 280 ps, resulting in a single-mode spontaneous emission coupling efficiency of 78%. It is believed that this structure will be useful in triggered photons sources for quantum cryptography.