The research is aimed at elucidating the behavior of various doped silicon-germanium alloys during rapid melting and solidification. The emphasis is on understanding the kinetic and thermodynamic behavior of rapidly moving interfaces, and the mechanisms by which phenomena such as crystal nucleation, crystal growth, and solute trapping occur. Laser melting and solidification are being studied. Characterization techniques include transient conductance, transient reflectance, transmission electron microscopy, and Rutherford Backscattering spectroscopy. Non-equilibrium molecular dynamics is being used to model the structure.