Regensburg 2019 – wissenschaftliches Programm
DY 9.9: Vortrag
Montag, 1. April 2019, 17:45–18:00, H19
Laser driven ultrafast crystallization of phase-change material Ge1Sb2Te4 — •Jingyi Zhu1, Shuai Wei2, Julian Merten2, Christoph Persch2, Lin Yang1, Matthias Wuttig2, and Paul H. M. van Loosdrecht1 — 1Physics institute 2, University of Cologne, 50937, Germany — 2I. Institute of Physics (IA), RWTH Aachen University, Aachen, 52074, Germany
Rapid and reversible switching between amorphous and crystalline phases of the phase-change materials are either used or very promising in a wide range of applications in the electronic, optoelectronic, and photonic memory devices. Here we use time-resolved spontaneous Raman spectra to monitor the ultrafast process of melting, bond softening and crystallization in the phase changing material Ge1Sb2Te4 upon laser excitation. We demonstrate ultrafast crystallization on a ps timescale by monitoring the transient formation of a well-defined phonon mode signaling the crystalline state emerging from a broad vibrational continuum typical for the amorphous state.