Strain and electric field induced low-symmetry states in Pb0.1Sr0.9TiO3.

Polarization rotation and occurrence of monoclinic and triclinic states were investigated in Pb_0.1Sr_0.9TiO₃. For this composition, the rhombohedral ground state may coexist with a tetragonal state close in free energy and become sensitive to electric and mechanical stimuli. The polarization path under an electric field and biaxial strain involves a monoclinic state, while for uniaxial strain the transition involves both monoclinic and triclinic states. Longitudinal and shear piezoelectric constants are enhanced in the induced monoclinic and tetragonal states, respectively. Low-temperature secondary peaks in the literature-reported dielectric spectra can be explained as polycrystalline average of dielectric tensor components of the low-symmetry structures. [ABSTRACT FROM AUTHOR]