Acoustic Ginzburg effect with nonclassical states of motion

Abstract

We explore the acoustic Ginzburg effect using a toy model consisting of a mass-spring chain and a detector. This effect is characterized by the excitation of the detector from its ground state and the generation of acoustic phonons in the chain from the vacuum when the detector travels at a uniform speed greater than the speed of sound. By analyzing a scenario where the detector travels in a superposition of two trajectories at different uniform velocities relative to the center of mass of the chain, we find that the reduced state of either the chain phonons or the detector's internal excitations differ when the detector is in a superposition of distinct trajectories as compared with a single localized trajectory. This distinction enables the chain or the detector to act as a quantum device to distinguish the detector's trajectory.