Light-induced Weyl semiconductor-to-metal transition mediated by Peierls instability
Honglie Ning, Omar Mehio, Chao Lian, Xinwei Li, Eli Zoghlin, Preston Zhou, Bryan Cheng, Stephen D. Wilson, Bryan M. Wong, David Hsieh
Abstract
Elemental tellurium is a strongly spin-orbit coupled Peierls-distorted semiconductor whose band structure features topologically protected Weyl nodes. Using time-dependent density functional theory calculations, we show that impulsive optical excitation can be used to transiently control the amplitude of the Peierls distortion, realizing a mechanism to switch tellurium between three states: Weyl semiconductor, Weyl metal, and non-Weyl metal. Further, we present experimental evidence of this inverse Peierls distortion using time-resolved optical second harmonic generation measurements. These results provide a pathway to multifunctional ultrafast Weyl devices and introduce Peierls systems as viable hosts of light-induced topological transitions.