On-chip indistinguishable photons using III-V nanowire/SiN hybrid integration

We demonstrate on-chip generation of indistinguishable photons based on a nanowire quantum dot. From a growth substrate containing arrays of positioned-controlled single dot nanowires, we select a single nanowire which is placed on a SiN waveguide fabricated on a Si-based chip. Coupling of the quantum dot emission to the SiN waveguide is via the evanescent mode in the tapered nanowire. Post-selected two-photon interference visibilities using continuous wave excitation above-band and into a p-shell of the dot were 100%, consistent with a single photon source having negligible multi-photon emission probability. Visibilities over the entire photon wavepacket, measured using pulsed excitation, were reduced by a factor of 5 when exciting quasi-resonantly and by a factor of 10 for above-band excitation. The role of excitation timing jitter, spectral diffusion and pure dephasing in limiting visibilities over the temporal extent of the photon is investigated using additional measurements of the coherence and linewidth of the emitted photons

On-demand single photon emission in the telecom C-band from nanowire-based quantum dots

Single photon sources operating on-demand at telecom wavelengths are required in fiber-based quantum secure communication technologies. In this work we demonstrate single photon emission from position-controlled nanowire quantum dots emitting at {\lambda} > 1530 nm. Using above-band pulsed excitation, we obtain single photon purities of g(2)(0) = 0.062. These results represent an important step towards the scalable manufacture of high efficiency, high rate single photon emitters in the telecom C-band