Effect of laser irradiation on structural, electrical, and optical properties of p‐mercury cadmium telluride

Single crystals of p‐Hc_1−xCd_xTe (x=0.16) were grown by the Bridgeman technique. The bulk single crystals were irradiated with laser pulse of various energy densities. A pulsed laser (Nd:YAG) capable of producing 10‐ns pulses of 0.53 μm wavelength (frequency doubled) with varying energy densities (2–50 mJ/cm²) was employed. dc conductivity and Hall coefficient measurements were made on the single crystal using the Van der Pauw technique in the temperature range 77–300 K for both as‐grown and laser‐irradiated samples. Also the x‐ray diffraction pattern and transmission measurements of the samples were taken at room temperature. Electrical studies shows that the p‐mercury cadmium telluride after the laser irradiation becomes n type and optical results show that the free‐carrier concentration after laser irradiation increases sharply so that there is negligibly small transmission. The x‐ray studies show that single crystal p‐type samples after laser irradiation undergo structural changes as well, introducing phases of CdTe, Hg, and Te in the lattice.