Quantum Stabilizer Codes for Correlated and Asymmetric Depolarizing Errors

TL;DR

This paper evaluates the performance of five- and seven-qubit quantum stabilizer codes under correlated and asymmetric depolarizing errors, revealing how error correlations and asymmetries influence their error correction effectiveness.

Contribution

It provides a detailed analysis of stabilizer code performance in correlated and asymmetric error environments, including error thresholds and the impact of error asymmetry.

Findings

Correlations lower code performance.

Asymmetry affects seven-qubit code but not five-qubit code.

Error thresholds are computed for different error models.

Abstract

We study the performance of common quantum stabilizer codes in the presence of asymmetric and correlated errors. Specifically, we consider the depolarizing noisy quantum memory channel and perform quantum error correction via the five and seven-qubit stabilizer codes. We characterize these codes by means of the entanglement fidelity as function of the error probability and the degree of memory. We show that their performances are lowered by the presence of correlations and we compute the error probability threshold values for codes effectiveness. Furthermore, we uncover that the asymmetry in the error probabilities does not affect the performance of the five-qubit code while it does affect the performance of the seven-qubit code which results less effective when considering correlated and symmetric depolarizing errors but more effective for correlated and asymmetric errors.