Optical properties of undoped and $Zn_4SnSe_6$ and $Zn_4SnSe_6:Co^{2+}$ Single Crystals

$Zn_4SnSe_6$ 및 $Zn_4SnSe_6:Co^{2+}$단결정의 광학적 특성연구

$Zn_4SnSe_6$ and $Zn_4SnSe_6:Co^{2+}$ single crystals were by the chemical transport reaction method. They crystallized in the monoclinic structure. The direct energy band gaps of the $Zn_4SnSe_6$ and $Zn_4SnSe_6:Co^{2+}$ single crystals at 289K were found to be 2.146eV and 2.042eV. Optical absorption due to impurity in the $Zn_4SnSe_6:Co^{2+}$ single crystal was observed and described as originating from the electron transition between energy leveles of $Co^{2+}$ sited at $T_d$ symmetry point.