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"Saving superconducting quantum processors from decay and correlated errors generated by gamma and cosmic rays", John Martinis, 2021

Reviewed June 12, 2025

Citation: Martinis, John M. "Saving superconducting quantum processors from decay and correlated errors generated by gamma and cosmic rays." npj Quantum Information 7.1 (2021): 90.

Web: https://arxiv.org/abs/2012.06137

Tags: Hardware


In this paper, John Martinis talks about how to reduce the disastrous effect of cosmic rays on superconducting devices. The proposal is to use thicker films of metal on part of the quasiparticle trap, and slightly changing the geometry of the trap. He then does lots of numerics to motivate why this works.

The best part of this paper is the concrete discussion of the mechanism by which cosmic rays affect superconducting chips, and what sort of length/time scales are relevant. The most important scale to keep in mind for me is that the effect of the ray lasts on the order of 16 microseconds. This is to be compared with the length of an error-correction cycle, which is on the order of 1 microsecond.