Quantum optics with quantum dots in photonic wires: Basics and application to “ultrabright” single photon sources

We review recent experimental and theoretical results, which highlight the strong interest of the photonic wire (PW) geometry for quantum optics experiments with solid-state emitters, and for quantum optoelectronic devices. By studying single InAs QDs embedded within single-mode cylindrical GaAs PW, we have noticeably observed a very strong (16 fold) inhibition of their spontaneous emission rate in the thin-wire limit, and a nearly perfect funnelling of their spontaneous emission into the guided mode for larger PWs. We present a novel single-photon-source based on the emission of a quantum dot embedded in an engineered PW, comprising a tapered tip so as to control the radiation pattern, and an integrated hybrid bottom mirror. Unlike microcavity-based devices, this source displays for the first time simultaneously a record-high efficiency (0.73 photon per pulse) and a very low g⁽²⁾ parameter. Numerical simulations show that an efficiency higher than 0.9 can be obtained for optimized structures, under either optical or electrical pumping.