Sensor-assisted fault mitigation in quantum computation

Abstract

We propose a method to assist fault mitigation in quantum computation through the use of sensors co-located near physical qubits. Specifically, we consider using transition edge sensors colocated on silicon substrates hosting superconducting qubits to monitor for energy injection from ionizing radiation, which has been demonstrated to increase decoherence in transmon qubits. We generalize from these two physical device concepts and explore the potential advantages of colocated sensors to assist fault mitigation in quantum computation. In the simplest scheme, colocated sensors beneficially assist rejection of calculations potentially affected by environmental disturbances. Investigating the potential computational advantage further required development of an extension to the standard formulation of quantum error correction. In a specific case of the standard three-qubit, bit-flip quantum error correction code, we show that given a 20% overall error probability per qubit, approximately 90% of repeated calculation attempts are correctable. However, when sensor-detectable errors account for 45% of overall error probability, the use of colocated sensors uniquely associated with independent qubits boosts the fraction of correct final-state calculations to 96%, at the cost of rejecting 7% of repeated calculation attempts.

EQC : Ensembled Quantum Computing for Variational Quantum Algorithms

“…Additionally, each QPU has its own unique noise profile that changes with frequent calibration. These volatile systems vary in spatial and temporal noise due to the imperfect manufacturing process [29], imperfections of gate implementation and control, and specific external interference [28], [31]. These noise compound with each other, increasing the overall probability of obtaining an erroneous outcome.…”