Spectral interferometric microscopy reveals absorption by individual optical nanoantennas from extinction phase.

ABSTRACT: Optical antennas transform light from freely propagating waves into highly localized excitations that interact strongly with matter. Unlike their radio frequency counterparts, optical antennas are nanoscopic and high frequency, making amplitude and phase measurements challenging and leaving some information hidden. Here we report a novel spectral interferometric microscopy technique to expose the amplitude and phase response of individual optical antennas across an octave of the visible to near-infrared spectrum. Although it is a far-field technique, we show that knowledge of the extinction phase allows quantitative estimation of nanoantenna absorption, which is a near-field quantity. To verify our method we characterize gold ring-disk dimers exhibiting Fano interference. Our results revea

SUBMITTER: Gennaro SD 

PROVIDER: S-EPMC4015323 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature