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arXiv · 0711.1555

Decoherence in quantum walks and quantum computers

Andrew P. Hines·P. C. E. Stamp
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Abstract

Decoherence is the major stumbling block in the realization of a large-scale quantum computer. Ingenious methods have been devised to overcome decoherence, but their success has been proven only for over-simplified models of system-environment interaction. Whether such methods will be reliable in the face of more realistic models is a fundamental open question. In this partly pedagogical article, we study two toy models of quantum information processing, using the language of \emph{quantum walks}. Decoherence is incorporated in 3 ways - by coupling to a noisy `projective measurement' system, and by coupling to oscillator and spin baths.

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Andrew P. Hines, P. C. E. Stamp. 2007-11-09. Decoherence in quantum walks and quantum computers. https://doi.org/10.1139/p08-016

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