Papers by Keyword: Self-Polarization

Abstract: Physical properties of self-polarized PbZr_1-xTi_xO₃ thin films with no preferential orientation were reported at 0.46 x 0.50 compositions. Structural analysis reveals coexistence between monoclinic-tetragonal and monoclinic-rhombohedral phases at 0.46 x 0.49, where the monoclinic phase is in majority over both tetragonal and rhombohedral phases. The dielectric permittivity (ε ́ = 447) shows a maximum at around x = 0.48. Asymmetries on macroscopic and local hysteresis loops confirm the self-polarization effect in the studied films.

Abstract: Self-polarized Pb(Ti,Zr)O3 thin films deposited under lead enriched conditions by multitarget reactive sputtering at low substrate temperatures are characterized by tetravalent B-site occupation of excess lead. The imaginary part of the dielectric constant of such films shows a relaxor-like behavior. Evidence of a Pb2+/Pb4+ mixed valence is given by the temperature and frequency dependence of the ac conductivity. PbO volatility starts to deplete the growing film at a critical temperature of 500°C and Pb4+ formation disappears.