Speaker
Description
The discovery that superconducting qubits are sensitive to ionizing radiation [1] has sparked interest beyond the quantum research community. Recent experiments, capable of detecting single interactions from cosmic muons [2, 3] and γ-rays [4], have highlighted the potential of these devices as a novel type of particle detector. As research in this field is still at an early stage, many questions remain open, especially regarding the propagation of phonons in the chip substrate and the reconstruction of the interaction point and energy deposited. In this framework, an important role is played by the study of correlated errors, i.e. simultaneous state decays of multiple qubits on the same chip.
In this contribution, we will present two fundamental building blocks for the investigation of correlated errors: a system for the multiplexed operation of up to four qubits, and a reset protocol for their simultaneous state preparation. The latter, in particular, is capable of preparing the qubits to different initial states, a flexibility uncommon in reset algorithms, and does not rely on specific hardware features, making it readily applicable to a wide range of superconducting qubit devices.
References:
1. Vepsäläinen et al., Impact of ionizing radiation on superconducting qubit coherence, Nature 584, 551-556 (2020), https://doi.org/10.1038/s41586-020-2619-8
2. Wilen et al., Correlated charge noise and relaxation errors in superconducting qubits, Nature 594, 369-373 (2021), https://doi.org/10.1038/s41586-021-03557-5
3. McEwen et al., Resolving catastrophic error bursts from cosmic rays in large arrays of superconducting qubits, Nat. Phys. 18, 107-111 (2022), https://doi.org/10.1038/s41567-021-01432-8
4. De Dominicis et al., Evaluating radiation impact on transmon qubits in above and underground facilities, EPJ Quantum Technol. (2026), https://doi.org/10.1140/epjqt/s40507-026-00490-2