Journal of Physics Condensed Matter

Electron dynamics in quantum gate operation

Andrew Kerridge, Anthony Henry Harker, Arthur Marshall Stoneham

Published Jun 19, 2007• 10 citations

Abstract

We model the evolving time-dependent electronic structure of a solid-state quantum gate as it performs basic quantum operations. Our time-dependent configuration-interaction method follows the evolution of two donor electron spin qubits interacting with a third, optically excited, control spin in an applied magnetic field, a possible realization of the basic component of a proposed quantum information processor. We identify unitary operations which approximately disentangle the control spin, and use them to construct high-accuracy two-electron operations that are locally equivalent to CNOT, SWAP and operations. From our evaluation of the accuracy of a set of candidate gates we estimate the residual entanglement of the control electron and overall gate operation times. These results attest to the feasibility of the silicon-based quantum gates proposed by Stoneham, Fisher and Greenland.

DOI: 10.1088/0953-8984/19/28/282201

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