Programmable Heisenberg-limit sensor from a nonlinear quantum energy pump

Abstract

We introduce a programmable Heisenberg-limited bosonic quantum sensor based on a nonlinear quantum energy pump, implemented with a Kerr-nonlinear resonator coupled to multiple high-Q microwave terminal resonators. For parameter estimation encoded in an arbitrary number-conserving Hamiltonian acting on the terminal modes, we analytically construct optimal sensing protocols that attain the maximal quantum Fisher information, including initial-state loading, probe preparation, and readout. For diagonal multiparameter signals, we further show that the full phase-sensing quantum Fisher information matrix can be obtained from correlations of locally measured physical terminal works, providing a signal-free calibration of the metrological resource. We numerically demonstrate the construction and its robustness using realistic circuit-QED parameters while including experimentally relevant imperfections.