Unidirectional light transmiission by two-layer nanostructures interacting via optical near-fields

Abstract

We experimentally demonstrate unidirectional light transmission through two-layer nanostructured materials considering that the horizontal-to-vertical-polarization conversion efficiency in the forward direction and the vertical-to-horizontal efficiency in the backward direction, which are usually equivalent due to optical reciprocity, are different. The different ways of transferring light momentum in the forward and backward directions via optical near-fields between the layers are responsible for the unidirectionality of light, which was theoretically investigated in our recent work [J. Opt. Soc. Am. B 31, 2404-2413]. With twolayer metal nanostructures experimentally fabricated via a repeated lift-off technique,

Self-assembly of fluorescent nanospheres on nanostructured azo molecular thin films and optical near-field excitation

“…A nano scale optical field with spatial resolution exceeding diffraction limit is manipulated by using nanospheres that can excite and transmit an optical near-field localizing near the nanospheres. [20][21][22] The optical energy at nano region can be transferred through the near-field optical interactions strongly dependent on the size and shape of the nanospheres.…”