Fano-like resonance in an optically driven atomic force microscope cantilever.

We observe Fano-like resonance in the vibration spectrum of an optically driven atomic force microscope cantilever system. The vibration of the cantilever is photothermally induced by exciting it with a 780-nm laser diode. The asymmetry of the resonance curve strongly depends on the position of the excitation spot along the central axis of the cantilever. By using a simple physical model, we could extract and analyze the hidden resonance and continuous components in the vibration spectrum.