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Universal Quantum Computation through Control of Spin-Orbit Coupling

D. Stepanenko·N. E. Bonesteel
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Abstract

We propose a method for quantum computation which uses control of spin-orbit coupling in a linear array of single electron quantum dots. Quantum gates are carried out by pulsing the exchange interaction between neighboring electron spins, including the anisotropic corrections due to spin-orbit coupling. Control over these corrections, even if limited, is sufficient for universal quantum computation over qubits encoded into pairs of electron spins. The number of voltage pulses required to carry out either single qubit rotations or controlled-Not gates scales as the inverse of a dimensionless measure of the degree of control of spin-orbit coupling.

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D. Stepanenko, N. E. Bonesteel. 2004-03-12. Universal Quantum Computation through Control of Spin-Orbit Coupling. https://doi.org/10.1103/physrevlett.93.140501

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