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Correlated errors can lead to better performance of quantum codes

A. Shabani
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Abstract

A formulation for evaluating the performance of quantum error correcting codes for a general error model is presented. In this formulation, the correlation between errors is quantified by a Hamiltonian description of the noise process. We classify correlated errors using the system-bath interaction: local versus nonlocal and two-body versus many-body interactions. In particular, we consider Calderbank-Shor-Steane codes and observe a better performance in the presence of correlated errors depending on the timing of the error recovery. We also find this timing to be an important factor in the design of a coding system for achieving higher fidelities.

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A. Shabani. 2007-03-15. Correlated errors can lead to better performance of quantum codes. https://doi.org/10.1103/physreva.77.022323

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