# Quantum paraelastic two-dimensional materials

## TL;DR

This study investigates the elastic energy landscape and phase transition of 2D tin oxide monolayers, revealing a quantum paraelastic phase that can be tuned via charge doping, with implications for 2D quantum materials.

## Contribution

It provides the first detailed analysis of quantum paraelasticity in 2D SnO monolayers using ab-initio MD and phonon mode analysis.

## Key findings

- Transition temperature of ~8.5 K identified.
- Soft phonon modes linked to structural transformation.
- Quantum paraelastic phase potentially tunable by charge doping.

## Abstract

We study the elastic energy landscape of two-dimensional tin oxide (SnO) monolayers and demonstrate a transition temperature of $T_c=8.5\pm 1.8$ K using ab-initio molecular dynamics (MD), that is close to the value of the elastic energy barrier $J$ derived from $T=0$ K density functional theory calculations. The power spectra of the velocity autocorrelation throughout the MD evolution permits identifying soft phonon modes likely responsible for the structural transformation. The mean atomic displacements obtained from a Bose-Einstein occupation of the phonon modes suggest the existence of a quantum paraelastic phase that could be tuned with charge doping: SnO monolayers could be 2D quantum paraelastic materials with a charge-tunable quantum phase transition.