Coupling-rate determination based on radiation-pressure-induced normal mode splitting in cavity optomechanical systems.

We theoretically propose a precise way to measure the coupling rate in an optomechanical system based on radiation-pressure-induced normal mode splitting. This all-optical method is effective in both weak and strong coupling regions. Simultaneously the vibrational frequency of the mechanical mode can also be detected easily in the reflected probe spectrum. The results are much useful for the extensive applications in optomechanical systems.