ABSTRACT
Realization of quantum optical circuits is at the heart of quantum photonic information processing. A long-standing obstacle, however, has been the absence of a suitable platform of single photon sources (SPSs). Such SPSs need to be in spatially ordered arrays and produce, on-demand, highly pure, and indistinguishable single photons with sufficiently uniform emission characteristics to enable controlled interference between photons from distinct sources underpinning functional quantum optical networks. We report on such a platform of SPSs based on a unique class of epitaxial quantum dots dubbed mesa-top single quantum dot. Under resonant excitation, the spatially ordered SPSs (without Purcell enhancement) show single photon purity of >99% [g(2)(0) ~ 0.015], high two-photon Hong-Ou-Mandel interference visibilities of 0.82 ± 0.03 (at 11.5 kelvin, without cavity), and spectral nonuniformity of <3 nanometers, within established locally tunable technology. Our platform of SPSs paves the path to creating on-chip scalable quantum photonic networks for communication, computation, simulation, sensing and imaging.
ABSTRACT
We demonstrate triggered single photon emission up to 77K from an ordered 5x8 array of InGaAs single quantum dots (SQDs). The SQDs are grown selectively on patterned mesa tops utilizing substrate-encoded size-reducing epitaxy (SESRE). It exploits designed surface-curvature stress gradients to preferentially direct atom migration from mesa sidewalls to the top during growth. The emission from the SQDs exhibits a g(2)(0) of 0.19 ± 0.03 at 8K and decent emission spectral uniformity (standard deviation <1% of emission wavelength). The SESRE QDs are inherently compatible with on-chip integrated light manipulation elements, thereby enabling a path towards integrated nanophotonic systems for quantum information processing.
