Analysis of optical constants and temperature-dependent absorption edge of GaS0.75Se0.25 layered crystals

Date

2017-06-01

Author

IŞIK, MEHMET
Hasanlı, Nızamı

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GaS0.75Se0.25 single crystals were optically characterized through transmission and reflection measurements in the wavelength range of 450-1000 nm. Derivative spectrophotometry analyses on temperature dependent transmittance spectra showed that band gap energies of the crystal increase from 239 eV (T=300 K) to 2.53 eV (T=10 K). Band gap at zero temperature, average phonon energy, electron phonon coupling parameter and rates of change of band gap energy with temperature were found from the temperature dependences of band gap energies under the light of different models reported in literature. Furthermore, the dispersion of room temperature refractive index was discussed in terms of single effective oscillator model. The refractive index dispersion parameters, namely oscillator and dispersion energies, zero-frequency refractive index, were determined as a result of analyses.

Subject Keywords

Semiconductors, Chalcogenides, Layered compounds, Crystal growth, Optical properties

URI

https://hdl.handle.net/11511/44166

Journal

MATERIALS RESEARCH BULLETIN

DOI

https://doi.org/10.1016/j.materresbull.2017.03.025

Collections

Department of Physics, Article

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Citation Formats

M. IŞIK and N. Hasanlı, “Analysis of optical constants and temperature-dependent absorption edge of GaS0.75Se0.25 layered crystals,” MATERIALS RESEARCH BULLETIN, pp. 280–284, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/44166.