A study of the optical and thermal properties of nonlinear mercury thiogallate crystals

The technology of growing mercury thiogallate crystals (HgGa₂S₄) is improved and high-quality bulk samples are produced. The basic optical and thermal properties of these crystals are studied. The transmission spectra of mercury thiogallate are measured and its nonlinear characteristics such as the quadratic susceptibility, tuning curves, and the optical-damage resistance are also determined. The specific heat and thermal conductivity of HgGa₂S₄ are measured. It is concluded that the combined properties of HgGa₂S₄ crystals can provide for them a leading position among the materials used in nonlinear-optical devices for mid-IR-frequency conversion.