Direct Measurement of Photoinduced Force for Nanoscale Infrared Spectroscopy and Chemical-Sensitive Imaging

Measurement of photoinduced mechanical responses by atomic force microscopy (AFM) because of sample infrared resonances enables chemical-sensitive microscopy with spatial resolution orders of magnitude better than the optical diffraction limit. However, the origin of noncontact photoinduced force between the AFM tip and the samples of infrared resonances is still under debate. To investigate its origin, we implemented synchronized infrared pulse...