Ultrafast laser-induced structural and electronic changes in solids

For over two decades the subject of laser-induced phase transitions in semiconductors has generated considerable interest. This interest is due to the technological importancee of semiconductors and the research in this field was in part driven by the hope of developing better methods for the annealing of ion-implated semiconductors. More recently, femtosecond laser pulses have made it possible to study highly non-equilibrium electron and lattice dynamics in seminconductors. In this talk we first present an overview of work on laser-induced structural and electronic changes in solids, and then describe recent work done in our group on GaAs.