RAMAN-SPECTRA OF HG1-XCDXTE ESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-0.18) IRRADIATED BY PULSED-LASER IN AIR

The effects of pulsed Nd:YAG laser irradiation of Hg1-xCdzTe (0.14 les s than or equal to z less than or equal to 0.18) in air are investigat ed by Raman spectroscopy. The samples are irradiated by pulse energy d ensities of 270 and 400 mJ/cm(2), with a pulse duration of 72 ns. In a comparison of the Raman spectra of nonirradiated and irradiated areas the following effects are noticed: the appearance of new Raman featur es at about 128 and 145 cm(-1) related to TeO2 created at the sample s urface, great suppression of the cluster mode A and vanishing of the s urface mode S_, broadening of TO1 & LO(1) mode, and slight reduction o f TO2 and LO(2) mode frequencies. These results are in agreement with the numerical results for composition changes in the surface layers of irradiated Hg1-xCdxTe.