Nonlinear phononics in 2D SnTe: a ferroelectric material with phonon dynamical amplification of electric polarization

TL;DR

This paper demonstrates that nonlinear phonon interactions in 2D SnTe can dynamically amplify electric polarization within subpicoseconds, enabling ultrafast control of ferroelectric and optical properties.

Contribution

It reveals a novel nonlinear phononics mechanism in 2D SnTe that enables ultrafast polarization control through phonon interactions, supported by first-principles simulations.

Findings

Nonlinear phonon interactions induce in-plane polarization oscillations.

Infrared-active phonon pumping leads to polarization amplification.

Potential for ultrafast ferroelectric and optical device applications.

Abstract

Ultrafast optical control of ferroelectricity using intense terahertz fields has attracted significant interest. Here we show that the nonlinear interactions between two optical phonons in SnTe, a two-dimensional in-plane ferroelectric material, enables a dynamical amplification of the electric polarization within subpicoseconds time domain. Our first principles time dependent simulations show that the infrared-active out-of-plane phonon mode, pumped to nonlinear regimes, spontaneously generates in-plane motions, leading to rectified oscillations in the in-plane electric polarization. We suggest that this dynamical control of ferroelectric material, by nonlinear phonon excitation, can be utilized to achieve ultrafast control of the photovoltaic or other non-linear optical responses.