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arXiv · 1408.7029

Structural phase transition of ternary high-k dielectric SmGdO3: Evidence from ADXRD and Raman Spectroscopic Studies

Yogesh Sharma·Pankaj Misra·Satyaprakash Sahoo·A. K. Mishra·S. M. Sharma·Ram S. Katiyar
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Abstract

High-pressure synchrotron based angle dispersive x-ray diffraction (ADXRD) studies were carried out on SmGdO3 (SGO) up to 25.7GPa at room temperature. ADXRD results indicated a reversible pressure-induced phase transition from ambient monoclinic to hexagonal phase at about 8.9 GPa. The observed pressure-volume data were fitted into the third order Birch-Murnaghan equation of state yielding zero pressure bulk moduli B0 = 132(22) and 177(22) GPa for monoclinic and hexagonal phases, respectively. Pressure dependent micro-Raman spectroscopy further confirmed the phase transition. The mode Gruneisen parameters and pressure coefficients for different Raman modes corresponding to each individual phase of SGO were calculated.

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Yogesh Sharma, Pankaj Misra, Satyaprakash Sahoo, A. K. Mishra, S. M. Sharma, Ram S. Katiyar. 2014-08-29. Structural phase transition of ternary high-k dielectric SmGdO3: Evidence from ADXRD and Raman Spectroscopic Studies. https://doi.org/10.1063/1.4913776

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