Anharmonicity of zone-center optical phonons: Raman scattering spectra of GaSe0.5S0.5 layered crystal

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2002-06-01

Author

Hasanlı, Nızamı
Kocabas, C
Ozkan, H

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The temperature dependencies (10-300 K) of the eight Raman-active mode frequencies and linewidths in GaSe0.5S0.5 layered crystal have been measured in the frequency range from 10 to 320 cm(-1). We observed softening and broadening of the optical phonon lines with increasing temperature. Comparison of the experimental data with the theories of the shift and broadening of the interlayer and intralayer phonon lines showed that the temperature dependencies can be explained by the contributions from thermal expansion, lattice anharmonicity and crystal disorder. The purely anharmonic contribution (phonon-phonon coupling) is found to be due to three-phonon processes. It was established that the effect of crystal disorder on the broadening of phonon lines is greater for GaSe0.5S0.5 than for binary compounds GaSe and GaS.

Subject Keywords

Mathematical Physics, Atomic and Molecular Physics, and Optics, Condensed Matter Physics

URI

https://hdl.handle.net/11511/38221

Journal

PHYSICA SCRIPTA

DOI

https://doi.org/10.1238/physica.regular.065a00534

Collections

Department of Physics, Article

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Citation Formats

N. Hasanlı, C. Kocabas, and H. Ozkan, “Anharmonicity of zone-center optical phonons: Raman scattering spectra of GaSe0.5S0.5 layered crystal,” PHYSICA SCRIPTA, pp. 534–538, 2002, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/38221.