Anharmonic behavior and structural phase transition in Yb{sub 2}O{sub 3}
- Vacuum and Pressure Standards, National Physical Laboratory, New Delhi-110012 (India)
The investigation of structural phase transition and anharmonic behavior of Yb{sub 2}O{sub 3} has been carried out by high-pressure and temperature dependent Raman scattering studies respectively. In situ Raman studies under high pressure were carried out in a diamond anvil cell at room temperature which indicate a structural transition from cubic to hexagonal phase at and above 20.6 GPa. In the decompression cycle, Yb{sub 2}O{sub 3} retained its high pressure phase. We have observed a Stark line in the Raman spectra at 337.5 cm{sup −1} which arises from the electronic transition between {sup 2}F{sub 5/2} and {sup 2}F{sub 7/2} multiplates of Yb{sup 3+} (4f{sup 13}) levels. These were followed by temperature dependent Raman studies in the range of 80–440 K, which show an unusual mode hardening with increasing temperature. The hardening of the most dominant mode (T{sub g} + A{sub g}) was analyzed in light of the theory of anharmonic phonon-phonon interaction and thermal expansion of the lattice. Using the mode Grüneisen parameter obtained from high pressure Raman measurements; we have calculated total anharmonicity of the T{sub g} + A{sub g} mode from the temperature dependent Raman data.
- OSTI ID:
- 22250713
- Journal Information:
- AIP Advances, Vol. 3, Issue 12; Other Information: (c) 2013 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
- Country of Publication:
- United States
- Language:
- English
Similar Records
Hybridization-driven strong anharmonicity in Yb-filled skutterudites
Raman scattering of rare earth sesquioxide Ho₂O₃: A pressure and temperature dependent study