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Decoherence by Correlated Noise and Quantum Error Correction

E. Novais·Harold U. Baranger
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Abstract

We study the decoherence of a quantum computer in an environment which is inherently correlated in time and space. We first derive the nonunitary time evolution of the computer and environment in the presence of a stabilizer error correction code, providing a general way to quantify decoherence for a quantum computer. The general theory is then applied to the spin-boson model. Our results demonstrate that effects of long-range correlations can be systematically reduced by small changes in the error correction codes.

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E. Novais, Harold U. Baranger. 2006-07-24. Decoherence by Correlated Noise and Quantum Error Correction. https://doi.org/10.1103/physrevlett.97.040501

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