Structure-property correlations, defect driven magnetism and anomalous temperature dependence of magnetic coercivity in PbTi1-xFexO3 (0 ≤x≤ 0.5) systems.

摘要: The search for new multiferroic materials is on the rise due to their potential applications in an advanced generation of highly efficient multifunctional devices. Here we report a series PbTi1−xFexO3 (0 ≤ x 0.5) samples prepared by solid-state reaction method. Structural analysis suggests that doping Fe introduces oxygen vacancies along c-axis (aliovalent substitution; Fe3+ → Ti4+), local distortions and microstrains PbTiO3 lattice which triggered partial structural transformation from tetragonal cubic. This has been confirmed using tools such as X-ray diffraction, Fourier Transform Infrared Spectroscopy, Raman spectroscopy, Mossbauer spectroscopy. presence was further refining site occupancies through Rietveld refinement. measurements ions exist 3+ state change coordination some octahedral tetrahedral points towards deficiency system. studies confirm all ordinary quasi phonon modes doped samples. overlapping weakening are related changes/transformation. modes’ shifting lower wavenumbers ascribed increase average atomic mass at Ti-sites. induced ferromagnetism system increases with content can be explained basis F-center exchange mechanism. Moreover, found anomalous temperature-dependent trend magnetic coercivity (decrease temperature decreased) terms low-temperature decrease effective anisotropy when effects magneto-electric coupling included. existence well-developed ferroelectric ferromagnetic hysteresis loops nature value dielectric constant 1 MHz attributed resistivity formation immobile defect dipole complexes.