Suppressing Electron-Phonon Coupling through Laser-Induced Phase Transition

Zhaowu Wang; Xiyu Li; Guozhen Zhang; Yi Luo; Jun Jiang

doi:10.1021/acsami.7b05480

Suppressing Electron-Phonon Coupling through Laser-Induced Phase Transition

ACS Appl Mater Interfaces. 2017 Jul 19;9(28):23309-23313. doi: 10.1021/acsami.7b05480. Epub 2017 Jul 7.

Authors

Zhaowu Wang^{1

2

3}, Xiyu Li², Guozhen Zhang², Yi Luo², Jun Jiang²

Affiliations

¹ School of Physics and Engineering, Henan University of Science and Technology , Luoyang City, Henan Province 471023, P. R. China.
² Hefei National Laboratory for Physical Sciences at the Microscale, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), CAS Key Laboratory of Mechanical Behavior and Design of Materials, School of Chemistry and Materials Science, University of Science and Technology of China , Hefei, Anhui 230026, P. R. China.
³ National Laboratory of Solid State Microstructures, Nanjing University , Nanjing 210093, P. R. China.

PMID: 28677384
DOI: 10.1021/acsami.7b05480

Abstract

Using first-principle calculations, we introduced a strategy of laser-induced phase transition that suppress electron-phonon couplings in crystal lattice. We explained unusual irreversible phase transitions in previous experiments on MoTe₂ and NaYF₄ crystals. Laser irradiations produced local heats in 2H-MoTe₂ and Hex NaYF₄, driving atom reorganizations toward new lattices. The reorganization with effective electron-phonon couplings continues with spontaneously generated heats, whereas a 1T'-MoTe₂ and a metastable cubic NaYF₄ phases were kept because of suppressed vibrational relaxations. Long time laser treatments create phases with weak electron-phonon couplings. Such irreversible transitions guarantee complete conversions, opening a new door to selective material modifications.

Keywords: electron−phonon coupling; first-principle; laser irradiation; local heat; phase transition.