M. P. Smaev, P. I. Lazarenko, M. E. Fedyanina, I. A. Budagovsky, A. Raab, I. V. Sagunova, S. A. Kozyukhin, “Formation of periodic two-phase structures on the surface of amorphous Ge$_2$Sb$_2$Te$_5$ films under the action of ultrashort laser pulses of different durations and repetition rates”, Optics and Spectroscopy, 2023, Volume 131, Issue 2,Pages 196

International Conference "Ultrafast Optical Phenomena" (UltrafastLight-2022), October 03-07, 2022, Moscow
Laser physics and laser optics

Formation of periodic two-phase structures on the surface of amorphous Ge$_2$Sb$_2$Te$_5$ films under the action of ultrashort laser pulses of different durations and repetition rates

M. P. Smaev^a, P. I. Lazarenko^b, M. E. Fedyanina^b, I. A. Budagovsky^a, A. Raab^b, I. V. Sagunova^b, S. A. Kozyukhin^cd

^a P. N. Lebedev Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia
^b National Research University of Electronic Technology, 124498 Zelenograd, Moscow, Russia
^c Tomsk State University, 634050 Tomsk, Russia
^d Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russia

Abstract: Phase change materials due to their high susceptibility to low-intensity light fields are extremely attractive for active microphotonics and integrated optics devices. As a result of fast phase switching, these materials change the refractive index in a wide spectral range, which has found application in information storage systems. In this work, we studied the formation of two-phase periodic structures consisting of alternating lines of amorphous and crystalline phases on the surface of thin-film Ge$_2$Sb$_2$Te$_5$ phase change materials exposed to ultrashort laser pulses. Periodic structures were formed at a wavelength of 1030 nm at different durations and repetition rates of light pulses. It has been established that the development of two-phase structures obtained at a constant energy fluence remains practically unchanged with an increase in the repetition rate from 10 kHz to 1 MHz, but a change in the pulse duration from 180 fs to 10 ps leads to a violation of the periodic structure due to the formation of extended continuously crystallized regions.

Keywords: chalcogenide films, Ge$_2$Sb$_2$Te$_5$, phase change materials, laser-induced periodic surface structures, two-phase structures.

Received: 20.12.2022
Revised: 13.01.2023
Accepted: 28.01.2023

DOI: 10.21883/OS.2023.02.55005.15-23