REGULATION OF A MICROCANTILEVER RESPONSE BY FORCE FEEDBACK

A feedback mechanism is used to control the forces incident on a mecha nical microcantilever as a function of the monitored cantilever motion . The control is effected by modifying the intensity of an auxiliary l aser beam that generates a thermally induced stress. The feedback is d esigned to reduce the effective resonance quality factor of the cantil ever. The resultant regulation of the cantilever motion is shown to im prove the measurement dynamics in atomic force microscopy, without sig nificantly degrading the signal to noise ratio.