Jamin interferometer and photothermal phenomena in microscopic scale

We propose a modified Jamin interferometer as the detection scheme for the photothermal spectroscopy for the microscopic volume of samples. The modification allows the two arms of the interferometer to be focused to separate spots thus applicable to a microscopic sample. The sample used is a thin film deposited on a glass substrate. The sampled volume is estimated to be 0.1 pl.