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Quantum computers based on electron spins controlled by ultra-fast, off-resonant, single optical pulses

Susan M. Clark·Kai-Mei C. Fu·Thaddeus D. Ladd·Yoshihisa Yamamoto
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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 broad-band optical pulses to rotate electron spins and provide the clock signal to the system. Non-local 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.

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Susan M. Clark, Kai-Mei C. Fu, Thaddeus D. Ladd, Yoshihisa Yamamoto. 2007-06-11. Quantum computers based on electron spins controlled by ultra-fast, off-resonant, single optical pulses. https://doi.org/10.1103/physrevlett.99.040501

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