Out-of-plane longitudinal sound velocity in SnS$_2$ determined via broadband time-domain Brillouin scattering

TL;DR

This study uses broadband time-domain Brillouin scattering to measure the out-of-plane longitudinal sound velocity and elastic constant of SnS₂, demonstrating a non-invasive optical method for characterizing 2D materials' elastic properties.

Contribution

It introduces a broadband time-domain Brillouin scattering technique to determine elastic properties of SnS₂, a 2D transition metal dichalcogenide, with precise optical measurements.

Findings

Out-of-plane longitudinal sound velocity v_L = 2950 ± 100 m/s

Elastic constant c_{33} = 39 ± 3 GPa

Demonstrates the potential of optical pump-probe methods for elastic property measurement

Abstract

Here we report time-resolved broadband transient reflectivity measurements performed in a single crystal of SnS$_2$. We made use of time-domain Brillouin scattering and a broadband probe to measure the out-of-plane longitudinal sound velocity $v_L$ = (2950 $\pm$ 100) m s$^{-1}$, in this semiconducting two-dimensional transition metal dichalcogenide. Our study illustrates the potential of this non-invasive all-optical pump-probe technique for the study of the elastic properties of transparent brittle materials and provides the value of the elastic constant $c_{33}$ = (39 $\pm$ 3) GPa.