  Quantum error correction works effectively only if the error rate of gate
operations is sufficiently low. However, some rare physical mechanisms can
cause a temporary increase in the error rate that affects many qubits; examples
include ionizing radiation in superconducting hardware and large deviations in
the global control of atomic systems. We refer to such rare transient spikes in
the gate error rate as error bursts. In this work, we investigate the
resilience of the surface code to generic error bursts. We assume that, after
appropriate mitigation strategies, the spike in the error rate lasts for only a
single syndrome extraction cycle; we also assume that the enhanced error rate
is uniform across the code block. Under these assumptions, and for a
circuit-level depolarizing noise model, we perform Monte Carlo simulations to
determine the regime in burst error rate and background error rate for which
the memory time becomes arbitrarily long as the code block size grows. Our
results indicate that suitable hardware mitigation methods combined with
standard decoding methods may suffice to protect against transient error bursts
in the surface code.
