  Recent studies in quantum computing have shown that quantum error correction
with large numbers of physical qubits are limited by ionizing radiation from
high-energy particles. Depending on the physical setup of the quantum
processor, the contribution of muons from cosmic sources can constitute a
significant fraction of these interactions. As most of these muons are
difficult to stop, we perform a conceptual study of a two-layer silicon pixel
detector to tag their hits on a solid-state quantum processor instead. With a
typical dilution refrigerator geometry model, we find that efficiencies greater
than 50% are most likely to be achieved if at least one of the layers is
operated at the deep-cryogenic (<1 K) flanges of the refrigerator. Following
this finding, we further propose a novel research program that could allow the
development of silicon pixel detectors that are fast enough to provide input to
quantum error correction algorithms, can operate at deep-cryogenic
temperatures, and have very low power consumption.
