International Conference "Ultrafast Optical Phenomena" (UltrafastLight-2022), October 03-07, 2022, Moscow
Physical optics

Kinetics of reversible phase transitions in Ge$_2$Sb$_2$Te$_5$ thin films at femtosecond laser irradiation

A. V. Kolchin^a, S. V. Zabotnov^b, D. V. Shuleiko^bc, P. I. Lazarenko^d, V. B. Glukhenkaya^d, S. A. Kozyukhin^d, P. K. Kashkarov<sup>be

a</sup> Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russia
^b Lomonosov Moscow State University, Faculty of Physics, 119991 Moscow, Russia
^c NTI Competence Center for Big Data Storage and Analysis, Lomonosov Moscow State University, 11999 Moscow, Russia
^d National Research University "Moscow Research Institute of Electronic Technology", Institute of Advanced Materials and Technologies, 124498 Zelenograd, Moscow, Russia
^e National Research Centre "Kurchatov Institute", 123182 Moscow, Russia

Abstract: Femtosecond laser irradiation of amorphous Ge$_2$Sb$_2$Te$_5$ thin films initiates reversible phase transitions. The amorphization and crystallization of Ge$_2$Sb$_2$Te$_5$ thin films were experimentally and theoretically confirmed. Electron and lattice temperatures kinetics during laser pulse duration were evaluated by two-temperature models calculations and experimental data. The dynamical changing of optical properties have been taking into account. Temperatures and cooling rates, which are necessary to initiate phase transitions by IR laser pulses with subpicosecond duration. The observed results open perspectives for improvement of Ge$_2$Sb$_2$Te$_5$ nanophotonical devices.

Keywords: Ge$_2$Sb$_2$Te$_5$ femtosecond laser technologies, Raman spectroscopy, phase transitions.

Received: 01.12.2022
Revised: 23.12.2022
Accepted: 28.01.2023

DOI: 10.21883/OS.2023.02.54996.10-23

Bibliographic databases:

•