Determination of optical constants and temperature dependent band gap energy of GaS0.25Se0.75 single crystals

IŞIK M., Gasanly N.

JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS, cilt.19, ss.374-378, 2017 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 19
  • Basım Tarihi: 2017
  • Dergi Adı: JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.374-378
  • Anahtar Kelimeler: Semiconductors, Band gap energy, Refractive index, ELECTRICAL-PROPERTIES, BRIDGMAN METHOD, GASE, GENERATION, GROWTH, FILMS
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Optical properties of GaS0.25Se0.75 single crystals were investigated by means of temperature -dependent transmission and room temperature reflection experiments. Derivative spectrophotometry analysis showed that indirect band gap energies of the crystal increase from 2.13 to 2.26 eV as temperature is decreased from 300 to 10 K. Temperature dependence of band gap energy was fitted under the light of theoretical expression. The band gap energy change with temperature and absolute zero value of the band gap energy were found from the analyses. The Wemple-DiDomenico single effective oscillator model and Sellmeier oscillator model were applied to the spectral dependence of room temperature refractive index to find optical parameters of the GaS0.25Se0.75 crystal. Chemical composition of the crystal was determined using the energy dispersive spectral measurements.