2014 American Physical Society. We adopt Ramsey's method of separated oscillatory fields to study coherences of the mechanical system in an optomechanical resonator. The high-resolution Ramsey fringes are observed in the emission optical field, when two pulses separated in time are applied. We develop a theory to describe the transient optomechanical behavior underlying the Ramsey fringes. We also perform the experimental demonstration using a silica microresonator. The method is versatile and can be adopted for different types of mechanical resonators and electromechanical resonators.
