Radiation pressure driven mechanical oscillation in deformed silica microspheres via free-space evanescent excitation.

Opto-mechanical effects including radiation pressure driven mechanical oscillations are observed through direct free-space evanescent excitation of whispering gallery modes in deformed silica microspheres. The simplicity, the robustness, and the relatively high coupling efficiency of free-space evanescent excitation open up new avenues for the exploration and application of opto-mechanical effects.