Giant in-plane optical and electronic anisotropy of tellurene: a quantitative exploration. Issue 34 (5th August 2022)

• Record Type: Journal Article
• Authors: Guo, Zhengfeng; Gu, Honggang; Fang, Mingsheng; Ye, Lei; Liu, Shiyuan
• Is Part Of: Nanoscale. Volume 14:Issue 34(2022)
• Page Start: 12238
• Page End: 12246
• Publication Date: 2022-08-05
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/d2nr03226k
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : Tellurene's giant in-plane optical anisotropy is quantitatively explored by complex refractive indices and dielectric functions, whose low-symmetry lattice structure gives rise to the electronic anisotropy and ultimately the optical anisotropy. Abstract : Tellurene's giant in-plane optical anisotropy brings richer physics and an extra degree of freedom to regulate its optical properties for designing novel and unique polarization-sensitive devices. Here, we quantitatively evaluate the in-plane optical anisotropy of tellurene and further reveal its physical origins by combining imaging Mueller matrix spectroscopic ellipsometry (MMSE) and first-principles calculations. The anisotropic complex refractive indices and dielectric functions, as well as the derived giant birefringence (|Δ n |max = 0.48) and dichroism (Δ k > 0.4), are accurately determined by imaging MMSE to quantitatively evaluate the in-plane optical anisotropy of tellurene. With density functional theory (DFT), tellurene's optical anisotropy is connected to its low-symmetry lattice structure with electrical anisotropy (including the anisotropic effective mass, partial charge density, and carrier mobility), leading to anisotropic electric polarization and ultimately optical anisotropy. This work provides a general and quantitative way to explore the optical anisotropy and also helps to comprehend the connection between the lattice structure and the optical anisotropy of tellurene and even other emerging low-symmetry materials, which will further promote their polarization-sensitive optical applications.