Universal phase dynamics in VO <sub>2</sub> switches revealed by ultrafast operando diffraction
Aditya Sood, Xiaozhe Shen, Yin Shi, Suhas Kumar, Su Ji Park, Marc Zajac, Yifei Sun, Long-Qing Chen, Shriram Ramanathan, Xijie Wang, William C. Chueh, Aaron M. Lindenberg
Abstract
A transient metal Vanadium dioxide is known to have a coupled structural and electronic transition that can be accessed through light, thermal, or electrical excitation. Ultrafast optical studies of this insulator-to-metal transition indicate that it is mediated by the formation of a transient metallic phase that retains the structure of the original insulating phase. Sood et al. show that a similar sequence occurs when the material is electrically excited with a series of voltage pulses. Using ultrafast electron diffraction, the researchers monitored the structure of a vanadium dioxide sample after excitation and found evidence of a metastable metallic phase that appears during the transition. Science , abc0652, this issue p. 352