Investigation of orthorhombic-to-tetragonal structural phase transition in(Ba1-xCax)(Zr0.05Ti0.95)O3 ferroelectric ceramics using micro-Raman scattering

Journal of Applied Physics (Impact Factor: 2.21). 01/2014; 115:044103. DOI: 10.1063/1.4863303

ABSTRACT Ferroelectric phase transition from orthorhombic-to-tetragonal phase was investigated in (Ba1-xCax)(Zr0.05Ti0.95)O3 ceramics [x=0.05, 0.08, 0.10] by micro-Raman scattering. The room temperature Raman scattering reveals the presence of orthorhombic-tetragonal phase co-existence by emergence of tetragonal phase with increase in calcium content. The temperature dependent Raman spectra also show similar cross-over with hardening of A(TO2) mode and disappearance of A(LO1) mode as system moves from orthorhombic-to-tetragonal phase. A thermal hysteresis of ~10K was observed in orthorhombic-to-tetragonal transition.

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