Band gap energy and valence band splitting of p-CdIn2Te4 crystal by photocurrent spectroscopy

Single crystals of p-CdIn2Te4 were grown by the Bridgman method without a seed crystal. From photocurrent measurements, it was found that three peaks, A, B, and C, correspond to the intrinsic transition from the valence band states of Gamma(7)(A), Gamma(6)(B), and Gamma(7)(C) to the conduction band state of Gamma(6), respectively. The crystal field splitting and the spin orbit splitting were found to be 0.2360 and 0.1119 eV, respectively. The temperature dependence of the CdIn2Te4 band gap energy was given by E-g(T)=E-g(0)-(9.43x10(-3))T-2/(2676+T). The E-g(0) was calculated to be 1.4750, 1.7110, and 1.8229 eV at the valence band states of Gamma(7)(A), Gamma(6)(B), and Gamma(7)(C), respectively. The band gap energy of p-CdIn2Te4 at room temperature was determined to be 1.2023 eV. (C) 2004 American Institute of Physics.