Grating-mediated wave guiding and holographic solitons

Abstract

We describe experimental and theoretical results of research on a new type of waveguide, the so-called grating-mediated waveguide (GMW) recently reported by our group. This waveguide structure relies on Bragg diffractions from a 1D grating giving rise to wave guiding in the direction normal to the grating wave vector. The structure consists of a shallow 1D grating having a bell- or trough-shaped amplitude in the confinement direction. We provide the theoretical analysis of the underlying wave-guiding mechanism along with experimental evidence for both the bell- and the trough-shaped waveguides. We investigate the robustness of grating-mediated wave guiding and suggest more elaborate, 2D structures, such as a GMW superlattice and a grating-mediated ring waveguide. Finally we discuss the relation between grating-mediated wave guiding and holographic solitons, which are the beams that are self-trapped solely by virtue of their jointly induced grating.