Promising single-photon emitter in the blue-green spectral range with an epitaxial CdSe/ZnSe nanowire quantum dot

We present a promising solid-state system able to emit triggered single-photons in the blue-green range up to room temperature. The active element is a CdSe Quantum Dot (QD) embedded in a bottom-up core-shell ZnSe nanowire grown by molecular beam epitaxy. The nanowire shell acts as a waveguide and confines the fundamental optical mode HE11, channeling the photons emitted by the QD along the nanowire axis. The nanowires have a base radius of 70-90 nm and a length of 5-6 μm with a conical ending that allows to adiabatically expands the guided mode and reduces the divergence angle. Photo-correlation measurements show anti-bunching with g⁽²⁾(0) values down to 0.3 at room temperature. Charged excitons degrade the emission properties at room temperature and we found that a neutral nanowire-quantum dot would emit single-photons with a brightness of 0.17 photon per pulse.