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Quantum information processing using quantum dot spins and cavity-QED

A. Imamoglu·D. D. Awschalom·G. Burkard·D. P. DiVincenzo·D. Loss·M. Sherwin·A. Small
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Abstract

The electronic spin degrees of freedom in semiconductors typically have decoherence times that are several orders of magnitude longer than other relevant timescales. A solid-state quantum computer based on localized electron spins as qubits is therefore of potential interest. Here, a scheme that realizes controlled interactions between two distant quantum dot spins is proposed. The effective long-range interaction is mediated by the vacuum field of a high finesse microcavity. By using conduction-band-hole Raman transitions induced by classical laser fields and the cavity-mode, parallel controlled-not operations and arbitrary single qubit rotations can be realized. Optical techniques can also be used to measure the spin-state of each quantum dot.

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A. Imamoglu, D. D. Awschalom, G. Burkard, D. P. DiVincenzo, D. Loss, M. Sherwin, A. Small. 1999-07-15. Quantum information processing using quantum dot spins and cavity-QED. https://arxiv.org/abs/quant-ph/9904096

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