Parity measurement in the strong dispersive regime of circuit quantum acoustodynamics (Part I)

Mechanical resonators are emerging as an important new platform for quantum science and technologies. By interfacing mechanical resonators with superconducting circuits, circuit quantum acoustodynamics (cQAD) can make a variety of important tools available for manipulating and measuring motional quantum states. We demonstrate direct measurements of the phonon number distribution and parity of non-classical mechanical states, which are useful for a variety of protocols such as quantum state preparation and error correction. In this talk, we present the design and characterization of a cQAD device operating in the strong dispersive regime, consisting of a superconducting qubit and a phonon mode in a bulk acoustic wave resonator. We show qubit spectroscopy measurements that resolve the phonon number distribution in classical and quantum states of the mechanical mode.