[23a-C206-1~8] 3.5 Ultrashort-pulse and high-intensity lasers (formerly 3.6)

[23a-C206-6] Ultrafast optical response and photoinduced phase transition of VTe₂

〇Hiroshi Tanimura¹, Norihiko Okamoto¹, Takao Homma¹, Yusuke Sato¹, Akihiro Ishii², Hitoshi Takamura², Tetsu Ichitsubo¹ (1.IMR, Tohoku Univ., 2.Tohoku Univ.)

Keywords:photoinduced phase transition, ultrafast phenomena, transition metal dichalcogenide

We have measured the ultrafast optical response of VTe₂, one of transition metal dichalcogenides, by femtosecond laser pump-probe spectroscopy. Under strongly excited conditions, coherent phonons originating from the high-temperature phase of VTe₂ were observed in the ultra-short time region of 3 ps after excitation.
We will report that this phase transition is a non-thermal process due to electronic excitation and proceeds by nucleation and growth processes.