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Algorithm-Based Analysis of Collective Decoherence in Quantum Computation

Shoko Utsunomiya·Cyrus P. Master·Yoshihisa Yamamoto
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Abstract

The information in quantum computers is often stored in identical two-level systems (spins or pseudo-spins) that are separated by a distance shorter than the characteristic wavelength of a reservoir which is responsible for decoherence. In such a case, the collective spin-reservoir interaction, rather than an individual spin-reservoir interaction, may determine the decoherence characteristics. We use computational basis states, symmetrized spin states and spin coherent states to study collective decoherence in the implementation of various quantum algorithms. A simple method of implementing quantum algorithms using stable subradiant states and avoiding unstable Dicke's superradiant states and Schrodinger's cat states is proposed.

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Shoko Utsunomiya, Cyrus P. Master, Yoshihisa Yamamoto. 2004-08-26. Algorithm-Based Analysis of Collective Decoherence in Quantum Computation. https://arxiv.org/abs/quant-ph/0408162

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