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arXiv · 1105.3737

Exciton-spin memory with a semiconductor quantum dot molecule

A. Boyer de la Giroday·N. Skold·R. M. Stevenson·I. Farrer·D. A. Ritchie·A. J. Shields
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Abstract

We report on a single photon and spin storage device based on a semiconductor quantum dot molecule. Optically excited single electron-hole pairs are trapped within the molecule and their recombination rate is electrically controlled over three orders of magnitude. Single photons are stored up to 1 microsecond and read out on a sub-nanosecond timescale. Using resonant excitation, the circular polarisation of individual photons is transferred into the spin state of electron-hole pairs with a fidelity above 80%, which does not degrade for storage times up to the 12.5ns repetition period of the experiment.

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A. Boyer de la Giroday, N. Skold, R. M. Stevenson, I. Farrer, D. A. Ritchie, A. J. Shields. 2011-05-18. Exciton-spin memory with a semiconductor quantum dot molecule. https://doi.org/10.1103/physrevlett.106.216802

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