Nonthermal Bonding Origin of a Novel Photoexcited Lattice Instability in SnSe.

TitleNonthermal Bonding Origin of a Novel Photoexcited Lattice Instability in SnSe.
Publication TypeJournal Article
Year of Publication2023
AuthorsY Huang, S Teitelbaum, S Yang, G De La Peña, T Sato, M Chollet, D Zhu, JL Niedziela, D Bansal, AF May, AM Lindenberg, O Delaire, M Trigo, and DA Reis
JournalPhysical Review Letters
Volume131
Issue15
Start Page156902
Date Published10/2023
Abstract

Lattice dynamics measurements are often crucial tools for understanding how materials transform between different structures. We report time-resolved x-ray scattering-based measurements of the nonequilibrium lattice dynamics in SnSe, a monochalcogenide reported to host a novel photoinduced lattice instability. By fitting interatomic force models to the fluence dependent excited-state dispersion, we determine the nonthermal origin of the lattice instability to be dominated by changes of interatomic interactions along a bilayer-connecting bond, rather than of an intralayer bonding network that is of primary importance to the lattice instability in thermal equilibrium.

DOI10.1103/physrevlett.131.156902
Short TitlePhysical Review Letters