Temperature dependent optical constants of amorphous Ge2Sb 2Te5 thin films

Vinod Madhavan, Ramakanta Naik, A. P A Faiyas, R. Ganesan, K. S. Sangunni

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

This study focuses on the temperature dependent optical band gap changes in the amorphous Ge2Sb2Te5 (GST) films. The behavior of the amorphous GST thin films at low temperatures has been studied. The band gap increment of around 0.2 eV is observed at low temperature (4.2 K) compared to room temperature (300 K). The band gap changes associated with the temperature are completely reversible. The other optical parameters like Urbach energy and Tauc parameter (B1/2) are studied for different temperatures and discussed. The observed changes in optical band gap (E g) are fitting to Fan's one phonon approximation. Phonon energy (Latin small letter h with strokeω) corresponding to a frequency of 3.59 THz is derived from Fan's approximation, which is close to the reported value of 3.66 THz.

Original languageEnglish
Pages (from-to)2172-2174
Number of pages3
JournalJournal of Non-Crystalline Solids
Volume356
Issue number41-42
DOIs
Publication statusPublished - 1 Sep 2010
Externally publishedYes

Fingerprint

Optical constants
Thin films
thin films
fans
Optical band gaps
Amorphous films
Temperature
Fans
temperature
Energy gap
strokes
approximation
energy
room temperature

Keywords

  • Chalcogenides (ChG)
  • GeSbTe (GST)
  • Optical band gap
  • Urbach energy

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Ceramics and Composites
  • Electronic, Optical and Magnetic Materials
  • Materials Chemistry

Cite this

Temperature dependent optical constants of amorphous Ge2Sb 2Te5 thin films. / Madhavan, Vinod; Naik, Ramakanta; Faiyas, A. P A; Ganesan, R.; Sangunni, K. S.

In: Journal of Non-Crystalline Solids, Vol. 356, No. 41-42, 01.09.2010, p. 2172-2174.

Research output: Contribution to journalArticle

Madhavan, Vinod ; Naik, Ramakanta ; Faiyas, A. P A ; Ganesan, R. ; Sangunni, K. S. / Temperature dependent optical constants of amorphous Ge2Sb 2Te5 thin films. In: Journal of Non-Crystalline Solids. 2010 ; Vol. 356, No. 41-42. pp. 2172-2174.
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