초록 |
The photoconductive ZnAl2Se4(112)/GaAs(100) layers were successfully grown by using the hot wall epitaxy method. From the Hall effect measurement, scattering at the high-temperature range (T>150 K) was mainly related to the acoustic phonon mode of lattice vibration and scattering at the low-temperature range (T<77 K) was superior to the dislocation scattering. In the photocurrent (PC) spectroscopy, we observed the A, B, and C peaks corresponding to 351.6 (3.5263), 343 (3.6147), and 333.5 nm (3.7177 eV) at 10 K, respectively. Three peaks of A, B, and C were caused by the band-to-band transitions from the valence band state of Γ4(z), Γ5(x), and Γ5(y) to the conduction band state of Γ1(s), respectively. Thus, a characteristic splitting of the valence band governed by the selection rule was first extracted through the method of PC spectroscopy. We noted that the crystal field splitting and spin orbit splitting were 0.088 and 0.103 eV, respectively. |