Role of the lattice in the light-induced insulator-to-metal transition in vanadium dioxide

TY - JOUR

T1 - Role of the lattice in the light-induced insulator-to-metal transition in vanadium dioxide

AU - Weber, Cedric

AU - Van Schilfgaarde, Mark

AU - Acharya, Swagata

PY - 2020/4/24

Y1 - 2020/4/24

N2 - Vanadium dioxide is a model material system which exhibits a metal-to-insulator transition at 67∘C. This holds potential for future ultrafast switching in memory devices but typically requires a purely electronic process to avoid the slow lattice response. The role of lattice vibrations is thus important, but it is not fully understood and it has been a long-standing source of controversy. We use ultrafast spectroscopy and ab initio quantum calculations to study the mechanism responsible for the transition. We identify an atypical Peierls vibrational mode associated with the transition and study its associated properties. Our findings led to theoretical prediction of a new electron-phonon pathway for a purely reversible electronic transition in a true bistable fashion under specific conditions. This transition is very atypical, as it involves purely chargelike excitations and requires only small nuclear displacement and might prompt future experimental investigations.

AB - Vanadium dioxide is a model material system which exhibits a metal-to-insulator transition at 67∘C. This holds potential for future ultrafast switching in memory devices but typically requires a purely electronic process to avoid the slow lattice response. The role of lattice vibrations is thus important, but it is not fully understood and it has been a long-standing source of controversy. We use ultrafast spectroscopy and ab initio quantum calculations to study the mechanism responsible for the transition. We identify an atypical Peierls vibrational mode associated with the transition and study its associated properties. Our findings led to theoretical prediction of a new electron-phonon pathway for a purely reversible electronic transition in a true bistable fashion under specific conditions. This transition is very atypical, as it involves purely chargelike excitations and requires only small nuclear displacement and might prompt future experimental investigations.

M3 - Article

SN - 2643-1564

VL - 2

SP - 023076

JO - Physical Review Research

JF - Physical Review Research

ER -