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arXiv · 1811.06481

Highly pure single photon emission from spectrally uniform surface-curvature directed mesa top single quantum dot ordered array

Abstract

Realizing ordered and spectrally uniform single photon source arrays integrable on-chip with light manipulating elements in scalable architecture lies at the core of building monolithic quantum optical circuits (QOCs). We demonstrate here a spatially-ordered 5 x 8 array of surface-curvature driven mesa-top GaAs(001)/InGaAs/GaAs single quantum dots (MTSQDs) that exhibit highly pure (~99% ) single photon emission as deduced from the measured g(2)(0) < 0.02 at 9.4K. Polarization-independent and polarization-resolved high resolution photoluminescence (PL) measurements show that these ordered and spectrally uniform QDs have neutral exciton emission with intrinsic linewidth ~ 10 ueV and fine structure splitting < 10 ueV, an important figure of merit for the use of QDs in QOCs. The findings point to the high potential of such MTSQD based single photon source arrays as a promising platform for on-chip scalable integration with light manipulating units (connected resonant cavity, waveguide, beam splitter, etc.) to enable constructing QOCs.

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Jiefei Zhang, Swarnabha Chattaraj, Siyuan Lu, Anupam Madhukar. 2018-11-15. Highly pure single photon emission from spectrally uniform surface-curvature directed mesa top single quantum dot ordered array. https://doi.org/10.1063/1.5080746

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