“…Entanglement of a mechanical oscillator with light has been predicted in a number of theoretical studies [5,55,56,57,58,59,60,61,62,63] and would be an intriguing demonstration of optomechanics in the quantum regime. These studies, as well as similar ones investigating entanglement among several mechanical oscillators [64,65,66,67,68,69,70,71,72], explore entanglement in the steady-state regime.…”