Tunable Chirality-dependent Nonlinear Electrical Responses in 2D Tellurium

TL;DR

This paper investigates how the chirality of 2D tellurium influences its nonlinear electrical responses, revealing opposite effects in enantiomers and proposing potential for chirality-based electronic devices.

Contribution

It demonstrates gate-tunable nonlinear electrical responses in 2D tellurium and links these effects to its chiral crystal structure, a novel insight for electronic device design.

Findings

Opposite signs of nonlinear responses in left- and right-handed tellurium

Observation of nonreciprocal electrical transport and nonlinear Hall effect

Chirality affects spin polarization and electrical responses

Abstract

Tellurium (Te) is an elemental semiconductor with a simple chiral crystal structure. Te in a two-dimensional (2D) form synthesized by solution-based method shows excellent electrical, optical, and thermal properties. In this work, the chirality of hydrothermally grown 2D Te is identified and analyzed by hot sulfuric acid etching and high-angle tilted high-resolution scanning transmission electron microscopy. The gate-tunable nonlinear electrical responses, including the nonreciprocal electrical transport in the longitudinal direction and the nonlinear planar Hall effect in the transverse direction, are observed in 2D Te under a magnetic field. Moreover, the nonlinear electrical responses have opposite signs in left- and right-handed 2D Te due to the opposite spin polarizations ensured by the chiral symmetry. The fundamental relationship between the spin-orbit coupling and the crystal symmetry in two enantiomers provides a viable platform for realizing chirality-based electronic devices by introducing the chirality degree of freedom into electron transport.