Ab initio molecular dynamics simulations of femtosecond-laser-induced anti-Peierls transition in antimony

Antimony is an interesting elemental crystal because, in its ground state, it is stabilized by a Peierls distortion. Here we perform density-functional-theory molecular dynamics simulations of this intriguing material before and after femtosecond-laser excitation using a simulation box with N = 864 atoms and periodic boundary conditions, where the atoms are treated in the Gamma-point approximation and the electrons are integrated over 8 k points. After an appropriate initialization of the atoms in the harmonic approximation we thermalize our system during 20 picoseconds. Then an intense femtosecond-laser excitation is simulated by instantaneously raising the electronic temperature to 8000 Kelvin. Our results show a laser-induced anti-Peierls transition.