Strong two-dimensional plasmon in Li-intercalated hexagonal boron-nitride film with low damping

TL;DR

This paper introduces a new class of layered 2D materials with exceptional plasmonic properties, demonstrating lithium-intercalated hexagonal boron-nitride as a promising low-loss plasmonic material with superior intensity to doped graphene.

Contribution

It proposes a novel layered material design with high-quality plasmons and a computationally efficient method for analyzing plasmon spectra in such materials.

Findings

Li-intercalated h-BN exhibits strong 2D plasmons with low damping.

The plasmon intensity surpasses that of heavily doped graphene.

A simple, accurate computational approach for plasmon analysis is developed.

Abstract

The field of plasmonics seeks to find materials with an intensive plasmon (large plasmon pole weight) with low Landau, phonon and other losses (small decay width). In this paper we propose a new class of materials that show exceptionally good plasmonic properties. These materials consist of van der Waals stacked 'plasmon active' layers (atomically thin metallic layers) and 'supporting' layers (atomically thin wide band gap insulating layers). One such material that can be experimentally realized - lithium intercalated hexagonal boron-nitride is studied in detail. We show that its 2D plasmon intensity is superior to intensity of well studied Dirac plasmon in heavy doped graphene which is hard to achieve. We also propose the method for computationally very cheap, but accurate analysis of plasmon spectra in such materials, based on one band tight-binding approach and effective background dielectric function.