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arXiv · 1011.2641

All-electrical coherent control of the exciton states in a single quantum dot

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

We demonstrate high-fidelity reversible transfer of quantum information from the polarisation of photons into the spin-state of an electron-hole pair in a semiconductor quantum dot. Moreover, spins are electrically manipulated on a sub-nanosecond timescale, allowing us to coherently control their evolution. By varying the area of the electrical pulse, we demonstrate phase-shift and spin-flip gate operations with near-unity fidelities. Our system constitutes a controllable quantum interface between flying and stationary qubits, an enabling technology for quantum logic in the solid-state.

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A. Boyer de la Giroday, A. J. Bennett, M. A. Pooley, R. M. Stevenson, N. Skold, R. B. Patel, I. Farrer, D. A. Ritchie, A. J. Shields. 2010-11-11. All-electrical coherent control of the exciton states in a single quantum dot. https://doi.org/10.1103/physrevb.82.241301

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