Atomic transformation pathways from terahertz radiation generated by shock-induced phase transformations

This work shows that detectable terahertz (THz) frequency radiation can be emitted when a wurtzite-structure crystal transforms to a rocksalt structure under shock compression on picosecond time scales. Information about the atomic-scale transformation pathway is contained in the sign of the emitted THz electric field and information about the kinetics is contained in the time dependence. This phenomenon provides an avenue to experimental measurement of microscopic transformation pathways in crystals on the shortest (picosecond) time scales.