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arXiv · 2302.01271

Quantum acoustic Fano interference of surface phonons

J. M. Kitzman·J. R. Lane·C. Undershute·N. R. Beysengulov·C. A. Mikolas·K. W. Murch·J. Pollanen
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Abstract

Quantum acoustic systems, which integrate surface or bulk phonons with superconducting qubits, offer a unique opportunity to investigate phononic $interference$ and $scattering$ processes in the quantum regime. In particular the interaction between a superconducting qubit and a phononic oscillator allows the qubit to sense the oscillator's excitation spectrum and underlying interference effects. Here we present measurements revealing Fano interference of a resonantly trapped piezoelectric surface acoustic wave (SAW) mode with a broad continuum of surface phonons in a system consisting of a SAW resonator coupled to a superconducting qubit. The experiments highlight the existence of additional weakly coupled mechanical modes and their influence on the qubit-phonon interaction and underscore the importance of phononic interference in quantum acoustic architectures that have been proposed for quantum information processing applications.

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J. M. Kitzman, J. R. Lane, C. Undershute, N. R. Beysengulov, C. A. Mikolas, K. W. Murch, J. Pollanen. 2023-02-02. Quantum acoustic Fano interference of surface phonons. https://doi.org/10.1103/physreva.108.l010601

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