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arXiv · 1609.00527

Path-dependent initialization of a single quantum dot exciton spin in a nano-photonic waveguide

Rikki J. Coles·David M. Price·Ben Royall·Edmund Clarke·Maurice S. Skolnick·Anthony M. Fox·Maxim M. Makhonin
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Abstract

We demonstrate a scheme for in-plane initialization and readout of a single exciton spin in an InGaAs quantum dot (QD) coupled to a GaAs nanobeam waveguide. The chiral coupling of the QD and the optical mode of the nanobeam enables spin initialization and readout fidelity approaching unity in magnetic field $B=1$ T and $\sim$0.9 without the field. We further show that this in-plane excitation scheme is independent of the incident excitation laser polarization and depends solely on the excitation direction. This scheme provides a robust in-plane spin excitation basis for a photon-mediated spin network for quantum information applications.

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Rikki J. Coles, David M. Price, Ben Royall, Edmund Clarke, Maurice S. Skolnick, Anthony M. Fox, Maxim M. Makhonin. 2016-09-02. Path-dependent initialization of a single quantum dot exciton spin in a nano-photonic waveguide. https://doi.org/10.1103/physrevb.95.121401

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