Tunable non-Gaussian mechanical states in a strongly coupled hybrid quantum system

Quantum states of motion are critical components in the second quantum revolution. To harness the unique features of mechanical modes in the quantum regime—such as long-lived modes, inherent non-linearities, and compact physical size — the preparation and control of non-trivial mechanical states is critical. In our work, we consider a collection of qubits coupled to an optomechanical system. Specifically, we explore the resulting non-Gaussian mechanical states in the strong coupling regime of the hybrid quantum system, characterized by significant Wigner negativities and large quantum Fisher Information. We find novel means to control the properties of the optomechanical system that results in non-trivial negative Wigner quasiprobability distribution and enhanced quantum Fisher information. We also show that they provide additional robustness to the system in the presence of weak dissipation. These non-Gaussian quantum states of motion realized by our hybrid quantum system are expected to be important for next-generation quantum metrology and quantum state transfer.