Speaker
Description
Recent work has shown that ionizing radiation incident on a superconducting qubit chip can cause phonon excitation and trapped charges. The phonons can generate non-equilibrium quasiparticles in the superconductor, which can tunnel across the junction and interact with the qubit energy. Trapped charges change the electric field environment in nearby qubits and are seen as charge noise in charge-sensitive qubits. High-energy interactions can cause these behaviors to manifest across multiple qubits on the same chip, correlated in space and time. We are studying these behaviors in various samples with different sensitivities: an array of weakly charge-sensitive aluminum qubits, an array of tantalum transmon qubits, and an array of SQUATs. These experiments are performed in our low background underground environment to study the effects of gamma radiation on these chips, specifically the NEXUS and QUIET underground testbeds at Fermilab. In this talk, we discuss how these studies can be used to calibrate the sensing potential of superconducting quantum sensors for particle detection.
