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arXiv · 1411.2654

A strain-tunable quantum dot embedded in a nanowire antenna

P. E. Kremer·A. C. Dada·P. Kumar·Y. Ma·S. Kumar·E. Clarke·B. D. Gerardot
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Abstract

We demonstrate an elastically-tunable self-assembled quantum dot in a nanowire antenna that emits single photons with resolution-limited spectral linewidths. The single-photon device is comprised of a single quantum dot embedded in a top-down fabricated nanowire waveguide integrated onto a piezoelectric actuator. Non-resonant excitation leads to static (fluctuating) charges likely at the nanowire surface, causing DC Stark shifts (inhomogeneous broadening); for low excitation powers, the effects are not observed and resolution-limited linewidths are obtained. Despite significant strain-field relaxation in the high-aspect-ratio nanowires, we achieve up to 1.2 meV tuning of a dot's transition energy. Single-photon sources with high brightness, resolution-limited linewidths, and wavelength tunability are promising for future quantum technologies.

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P. E. Kremer, A. C. Dada, P. Kumar, Y. Ma, S. Kumar, E. Clarke, B. D. Gerardot. 2014-11-10. A strain-tunable quantum dot embedded in a nanowire antenna. https://doi.org/10.1103/physrevb.90.201408

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