Four-wave mixing spectroscopy of metastable centers in semiconductors

An application of the continuous wave four-wave mixing technique for studyi ng the nature of metastable centers in semiconductors is presented. The res ults of measurements of the four-wave mixing scattering efficiency dependen ce on the intensity of the write beams for CdF2 crystals doped with In or G a are presented and theoretically explained. It is also shown that the obta ined results can be used for identification of the sign of the Hubbard corr elation energy of metastable centers in semiconductors. (C) 2001 American I nstitute of Physics.