Theory for the time-dependence of the response of covalent solids to laser irradiation

We present a theory for the time-dependent response of Si, Ge, C and Ga As in which an electron–hole pair plasma has been excited by an intense laser pulse. The hot electrons cause a fast loss of cubic lattice symmetry and subsequent melting within 100 to 500 fs. The theory is in good agreement with experiments and serves as a basis for the general problem of strong interaction of light with matter.