Photoluminescence and spectroscopic ellipsometry of single crystal MnGa2S4

This paper reports the synthesis, photoluminescence (PL) and spectroscopic ellipsometry (SE) studies of MnGa₂S₄ single crystal. Here, the study of photoluminescence properties of the compound in the visible and infrared regions and the calculation of colour coordinates were widely investigated. In the present work, previously observed optical transitions in various works were observed in PL spectra. A higher correlated colour temperature value of 4353 K suggests that this material is suitable for light-emitting diode applications. Ellipsometry measurements were performed on the samples using a variable angle spectroscopic ellipsometer in the spectral range of 1–6 eV. The ordinary refractive index has a peculiarity at ~3.469 eV and the extraordinary component at 3.751 eV. These peculiarities in the line shape resemble the critical point M0 for the 2D case. The values of these critical points correspond to the direct band gap value.