Laser-Controlled Nonlinear Hall Effect in Tellurium Solids via Nonlinear Phononics

TL;DR

This study demonstrates how strong THz laser excitation can control the nonlinear Hall effect in tellurium by inducing lattice distortions and modifying its electronic and topological properties, including Berry curvature and current direction.

Contribution

It reveals a novel method to manipulate topological transport properties in solids using nonlinear phononics driven by THz lasers, combining first-principles calculations and dynamical simulations.

Findings

THz laser induces lattice distortion and phase transition in tellurium.

Nonlinear Hall effect can be modulated and reversed with electron doping.

Lattice dynamics influence topological electronic properties.

Abstract

A Terahertz (THz) laser with strong strength could excite more than one phonons and induce a transient lattice distortion termed as nonlinear phononics. This process allows dynamic control of various physical properties, including topological properties. Here, using first-principles calculations and dynamical simulations, we demonstrate that THz laser excitation can modulate the electronic structure and the signal of nonlinear Hall effect in elemental solid tellurium (Te). By strongly exciting the chiral phonon mode, we observe a non-equilibrium steady state characterized by lattice distortion along the breathing vibrational mode. This leads to a transition of Te from a direct to an indirect semiconductor. In addition, the energy dispersion around the Weyl point is deformed, leading to variations in the local Berry curvature dipole. As a result, the nonlinear Hall-like current in Te can be modulated with electron doping where the sign of current could be reversed under a strong THz laser field. Our results may stimulate further research on coupled quasiparticles in solids and the manipulation of their topological transport properties using THz lasers.