Low-temperature photoluminescence spectra of layered semiconductor TlGaS2

Photoluminescence (PL) spectra of TlGa& layered single crystals were studied in the wavelength region 500-860 nm and in the temperature range 9.5-293 K. We observed a total of three PL bands centered at 568 nm (2.183 eV, A-band), 718 nm (1.727 eV, B-band) and 780 nm (1.590 eV, C-band) at various temperatures. We have also studied the variations of the A- and B-band intensities vs excitation laser density in the range from 7 X 10e2 to 9 W cm-‘. The A- and B-bands were found to be due to radiative transitions from the deep donor levels located at 0.362 and 0.738 eV below the bottom of the conduction band to the shallow acceptor levels at 0.005 and 0.085 eV located above the top of the valence band, respectively. The proposed energy-level diagram permits us to interpret the recombination processes in TlGa& layered single crystals.
Citation Formats
N. Hasanlı, A. Aydinli, A. Bek, and İ. Ö. Yılmaz, “Low-temperature photoluminescence spectra of layered semiconductor TlGaS2,” pp. 21–24, 1998, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/28461.