Photothermal imaging for single nanoparticle using near-common path interferometer

This paper describes a method to detect apparently magnified image of nanoparticles by the photothermal effect and using near-common path interferometer for single biomolecule detection in the field of molecular biology. Nanoparticles can be detected by the photothermal effect which is converting light energy to thermal energy. The photothermal effect makes it possible to magnify an image of nanoparticles. Its image can be detected using a near-common path interferometer for robust detection and performing phase analysis based on the Fourier transform method for real-time detection. This paper reports that the phase of interference fringe changed by the photothermal effect was obtained using the Fourier transform method to detect positions of carbon microparticles in video rate.