Scattering spectroscopy of molecules at nanometer resolution

A new form of optical spectroscopy is demonstrated whereby the local scattering from the interaction between a nanometer size probe tip and a sample is measured as a function of wavelength. We show images of viruses and molecules at molecular spatial resolution and demonstrate how the image contrast varies with wavelength. To first approximation, the contrast as a function of wavelength varies in the same way as the local polarizability of the sample © 1996 American Institute of Physics.