Transport in Sawtooth photonic lattices

TL;DR

This paper explores the transport properties of a photonic Sawtooth lattice, demonstrating flat band-induced transport inhibition and localized surface states through theoretical and experimental methods.

Contribution

It provides the first experimental realization and analysis of transport phenomena in a photonic Sawtooth lattice, highlighting flat band effects and surface states.

Findings

Observation of flat band leading to transport inhibition

Experimental demonstration of localized Shockley surface states

Identification of different transport regimes in the lattice

Abstract

We investigate, theoretically and experimentally, a photonic realization of a Sawtooth lattice. This special lattice exhibits two spectral bands, with one of them experiencing a complete collapse to a highly degenerate flat band for a special set of inter-site coupling constants. We report the ob- servation of different transport regimes, including strong transport inhibition due to the appearance of the non-diffractive flat band. Moreover, we excite localized Shockley surfaces states, residing in the gap between the two linear bands.