The Optical Properties and Plasmonics of Anisotropic 2-Dimensional Materials

TL;DR

This review explores the optical properties and hyperbolic plasmonic behavior of anisotropic 2D materials, especially black phosphorus, highlighting their potential in nanophotonics and optoelectronic applications.

Contribution

It provides a comprehensive overview of the optical and plasmonic properties of anisotropic 2D materials, emphasizing hyperbolic plasmons and potential applications.

Findings

Hyperbolic plasmons predicted in black phosphorus films

Anisotropic 2D materials offer tunable optical properties

Potential for novel nanophotonic devices

Abstract

In the fast growing two-dimensional (2D) materials family, anisotropic 2D materials, with their intrinsic in-plane anisotropy, exhibit a great potential in optoelectronics. One such typical material is black phosphorus (BP), with a layer-dependent and highly tunable band gap. Such intrinsic anisotropy adds a new degree of freedom to the excitation, detection and control of light. Particularly, hyperbolic plasmons with hyperbolic q-space dispersion are predicted to exist in BP films, where highly directional propagating polaritons with divergent densities of states are hosted. Combined with a tunable electronic structure, such natural hyperbolic surfaces may enable a series of exotic applications in nanophotonics. In this review, the anisotropic optical properties and plasmons (especially hyperbolic plasmons) of BP are discussed. In addition, other possible 2D material candidates (especially anisotropic layered semimetals) for hyperbolic plasmons are examined. This review may stimulate further research interest in anisotropic 2D materials and fully unleash their potential in flatland photonics.