Long-wavelength lattice vibrations of Ag3In5Se9 and Ag3In5Te9 single crystals: An inversion of LO- and TO-mode frequencies

Date

2016-07-10

Author

Hasanlı, Nızamı

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Infrared (IR) reflectivities are registered in the frequency range of 50-2000 cm(-1) for Ag3In5Se9 and Ag3In5Te9 single crystals grown by Bridgman method. Three infrared active modes are detected in spectra. The optical parameters, real and imaginary parts of the dielectric function, the function of energy losses, refractive index, absorption index and absorption coefficient were calculated from reflectivity experiments. The frequencies of transverse and longitudinal optical modes (TO and LO modes) and oscillator strength were also determined. The bands detected in infrared spectra were tentatively attributed to various vibration types (valence and valence-deformation). The inversion of LO- and TO-mode frequencies of the sandwiched pair was observed for studied crystals.

Subject Keywords

Semiconductors, Chalcogenides, Optical properties, Infrared reflection

URI

https://hdl.handle.net/11511/35268

Journal

MODERN PHYSICS LETTERS B

DOI

https://doi.org/10.1142/s0217984916502298

Collections

Department of Physics, Article

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Citation Formats

N. Hasanlı, “Long-wavelength lattice vibrations of Ag3In5Se9 and Ag3In5Te9 single crystals: An inversion of LO- and TO-mode frequencies,” MODERN PHYSICS LETTERS B, pp. 0–0, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35268.