- Markus Selmke: Molecular Nanophotonics Group, Institute of Experimental Physics I, University of Leipzig, 04103 Leipzig, Germany.
We demonstrate that the quantum-mechanical description of Rutherford scattering has a photonic counterpart in a new form of single particle photothermal microscopy. Using a split detector we provide experimental evidence that photons are deflected by a photothermal potential that is created by a local refractive index change around a heated nanoparticle. The deflection experienced is shown to be the analog to the deflection of a massive particle wave packet in unscreened spinless Coulomb scattering. The experimentally found focal detection geometry reveals a lateral split feature which will allow new correlation-based velocimetry experiments of absorbing particles with ultrahigh sensitivity.