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arXiv:quant-ph/0610152 · Physical Review Letters

Quantum Computers Based on Electron Spins Controlled by Ultrafast Off-Resonant Single Optical Pulses

Susan Clark, Kai‐Mei C. Fu, Thaddeus D. Ladd, Y. Yamamoto

Published Jul 23, 2007• 98 citations
arXivHTMLPDF

Abstract

We describe a fast quantum computer based on optically controlled electron spins in charged quantum dots that are coupled to microcavities. This scheme uses broadband optical pulses to rotate electron spins and provide the clock signal to the system. Nonlocal two-qubit gates are performed by phase shifts induced by electron spins on laser pulses propagating along a shared waveguide. Numerical simulations of this scheme demonstrate high-fidelity single-qubit and two-qubit gates with operation times comparable to the inverse Zeeman frequency.

DOI
10.1103/physrevlett.99.040501

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