Surface Bound States in the Continuum in Dyakonov Structures

TL;DR

This paper demonstrates the existence of surface bound states in the continuum at interfaces of homogeneous media, specifically in Dyakonov structures, revealing new ways to create such states in various materials.

Contribution

It shows that SBICs can occur at homogeneous interfaces and introduces leaky Dyakonov states at interfaces with opposite anisotropy signs, expanding the understanding of SBICs.

Findings

Leaky Dyakonov states exist at homogeneous interfaces with opposite anisotropy signs.

Breaking anisotropy-symmetry enables formation of guided states and SBICs.

Potential to create SBICs in new classes of materials and metamaterials.

Abstract

Surface bound states in the continuum (SBICs) have been found to occur in diverse settings, but so far always at the interface of non-homogeneous media, such as discrete lattices or periodic systems. Here we show that they can also exist at the interface of homogeneous media, resulting in unique SBICs. Specifically, we found that, contrary to general belief, leaky Dyakonov states exist at the interface between materials that exhibit opposite signs of anisotropy. In addition, properly breaking the anisotropy-symmetry leads to the formation of both guided states and also SBICs embedded within the continuum. A direct implication of our finding is the possibility to create SBICs and Dyakonov states in a whole new class of materials and metamaterials.