Investigation of orthorhombic-to-tetragonal structural phase transition in (Ba_(1-x)Ca_x)(Zr_(0.05)Ti_(0.95))O_3 ferroelectric ceramics using micro-Raman scattering

摘要

Ferroelectric phase transition from orthorhombic-to-tetragonal phase was investigated in (Ba_(1-x)Ca_x)(Zr_(0.05)Ti_(0.95))O_3 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(TO_2) mode and disappearance of A(LO_1) mode as system moves from orthorhombic-to-tetragonal phase. A thermal hysteresis of ～10K was observed in orthorhombic-to-tetragonal transition.