MULTIPHOTON PUMPING IN A LARGE BAND-GAP SEMICONDUCTOR-LASER

Population inversion in a large band gap semiconductor, e.g., ZnSe or ZnS, could be achieved by irradiating it with a picosecond Nd: glass l aser of power density exceeding 30 GW/cm(2). The laser field induces v alence band electrons to tunnel to the conduction band, creating elect ron-hole plasma. The electron-hole recombination produces coherent rad iation at ultraviolet wavelength. Nonlocal effects have a significant influence over the gain. (C) 1998 American Institute of Physics.