A microwave scattering spectral method to detect the nanomechanical vibrations embedded in a superconducting qubit

TL;DR

This paper introduces a novel microwave scattering spectral method to detect and characterize nanomechanical vibrations embedded in superconducting qubits, offering an alternative to emission spectral probes for quantum sensing.

Contribution

It proposes a new scattering spectral approach to analyze nanomechanical resonators within superconducting qubits, enabling effective determination of vibrational features and physical parameters.

Findings

Spectral dips and peaks reveal vibrational features.

Method effectively determines vibrational frequency and displacements.

Feasible with current technology for quantum metrology applications.

Abstract

Nanomechanical resonators (NMRs), as the quantum mechanical sensing probers, have played the important roles for various high-precision quantum measurements. Differing from the previous emission spectral probes (i.e., the NMR modified the atomic emission), in this paper we propose an alternative approach, i.e., by probing the scattering spectra of the quantum mechanical prober coupled to the driving microwaves, to characterize the physical features of the NMR embedded in a rf-SQUID based superconducting qubit. It is shown that, from the observed specifical frequency points in the spectra, i.e., either the dips or the peaks, the vibrational features (i.e., they are classical vibration or quantum mechanical one) and the physical parameters (typically such as the vibrational frequency and displacements) of the NMR can be determined effectively. The proposal is feasible with the current technique and should be useful to design the desired NMRs for various quantum metrological applications.