Detection of nonthermal molting by ultrafast X-ray diffraction

Using ultrafast, time-resolved, 1.54 angstrom x-ray diffraction, thermal an d ultrafast nonthermal melting of germanium, involving passage through none quilibrium extreme states of matter, was observed. Such ultrafast, optical- pump, x-ray diffraction probe measurements provide a way to study many othe r transient processes in physics, chemistry, and biology, including direct observation of the atomic motion by which many solid-state processes and ch emical and biochemical reactions take place.