Resonance Raman Scattering in TlGaSe₂ Crystals

Abstract

The resonance Raman scattering for geometries ( ) and ( ) at temperature 10 K and infrared reflection spectra in ‖ and ‖ polarizations at 300 K were investigated. The number of ( ) and ( ) symmetry vibrational modes observed experimentally and calculated theoretically agree better in this case than when TlGa 2 Se 4 crystals belong to 2ℎ symmetry group. The emission of resonance Raman scattering and excitonic levels luminescence spectra overlap. The lines in resonance Raman spectra were identified as a combination of optical phonons in Brillouin zone center.