Saturday, 10 June, 2006
Infrared spectroscopic mapping of single nanoparticles and viruses at nanoscale resolution
M. Brehm, T. Taubner, R. Hillenbrand, and F. Keilmann -
Nano Letters 6, 1307(2006)
We demonstrate that scattering near-field microscopy (s-SNOM) can determine infrared "fingerprint" spectra of individual poly(methyl methacrylate) nanobeads and viruses as small as 18 nm. Amplitude and phase spectra are found surprisingly strong, even at a probed volume of only 10-20 l, and robust in regard to particle size and substrate. This makes infrared spectroscopic s-SNOM a versatile tool for chemical and-in the case of protein-secondary-structure identification.