Deep Subwavelength Topological Edge State in a Hyperbolic Medium

TL;DR

This paper reports the first experimental demonstration of deep subwavelength topological edge states in hyperbolic media, achieved through periodic modulation of phonon polaritons in Van der Waals heterostructures, advancing nanophotonics applications.

Contribution

It provides the first experimental proof of deep subwavelength topological edge states in hyperbolic media using Van der Waals heterostructures, enabling broader material and application integration.

Findings

First experimental demonstration of deep subwavelength topological edge states.

Implementation of periodic modulation of hyperbolic phonon polaritons.

Potential for broad material substitution and application in nanophotonics.

Abstract

Topological nanophotonics presents the potential for cutting-edge photonic systems, with a core aim revolving around the emergence of topological edge states. These states are primed to propagate robustly while embracing deep subwavelength confinement that defies diffraction limits. Such attributes make them particularly appealing for nanoscale applications, where achieving these elusive states has remained challenging. We unveil the first experimental proof of deep subwavelength topological edge states by implementing periodic modulation of hyperbolic phonon polaritons within a Van der Waals heterostructure. This finding represents a significant milestone in the field of nanophotonics, and it can be directly extended to and hybridized with other Van der Waals materials in various applications. The extensive scope for material substitution facilitates broadened operational frequency ranges, streamlined integration of diverse polaritonic materials, and compatibility with electronic and excitonic systems.