Decoherence in quantum walks and quantum computers
arXiv:0711.1555 · doi:10.1139/P08-016
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.
8 pages, 3 figures; to appear in Theory Canada 3 special issue if the Canadian Journal of Physics
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Cited by in corpus (5)
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- Quantum correlations of identical particles subject to classical environmental noise
- Implementation of the quantum walk step operator in lateral quantum dots
- Environment-induced mixing processes in quantum walks
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