OPTICAL PHONONS IN GAS1-XSEX LAYER MIXED-CRYSTALS

Date

1983-01-01

Author

Hasanlı, Nızamı
MELNIK, NN
RAGIMOV, AS

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Measurements are made of polarized Raman scattering and infrared reflection spectra of twenty two compositions of GaS1‐xSex layer mixed crystals grown by the Bridgman method. Besides the usual one‐mode and two‐mode behaviours of phonon modes, a number of more complex dependences characterized by the appearance of additional bands in the spectra of mixed crystals are observed. Their appearance is accounted for by the uncovering of the Brillouin zone due to the disturbance of the periodicity of the crystal lattice of mixed crystals. Specifically, for modes with a low dispersion in the Brillouin zone the additional modes are interpreted as vibrations of cells having mixed compositions. A number of anomalies are revealed in the concentration dependences of intensities and frequencies of optical phonons, which are attributed to the β → γ and γ → ϵ polytype transformations at x ≈ 0.6 and x ≈ 0.97, respectively.

Subject Keywords

Electronic, Optical and Magnetic Materials, Condensed Matter Physics

URI

https://hdl.handle.net/11511/42854

Journal

PHYSICA STATUS SOLIDI B-BASIC RESEARCH

DOI

https://doi.org/10.1002/pssb.2221200115

Collections

Department of Physics, Article

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Citation Formats

N. Hasanlı, N. MELNIK, and A. RAGIMOV, “OPTICAL PHONONS IN GAS1-XSEX LAYER MIXED-CRYSTALS,” PHYSICA STATUS SOLIDI B-BASIC RESEARCH, pp. 137–147, 1983, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42854.