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One of the negative effects of ferroelectric applications, particularly for electrocaloric effect (ECE) applications, is temperature hysteresis (ΔTHyst). Temperature hysteresis is the difference between the temperatures corresponding to the maximum dielectric permittivity in heating and cooling modes. The value of ΔTHyst is commensurate with the value of the ECE temperature change. The ECE is a phenomenon in which a material shows a reversible temperature change under an applied electric field. The aim of this work is to study the possibilities of temperature hysteresis reduction by varying the ceramic sintering temperature, changing the stoichiometry of BaxSr1-xTiO3 solid solutions, and changing the rate of the heating-cooling cycle. [ABSTRACT FROM AUTHOR]

We report the preparation and characterization of vanadium substituted four-layer Aurivillius compound Bi5Fe1.5V0.5Ti2O15 using spin coating method. Ferroelectricity in the prepared films are confirmed from the well saturated polarization vs electric field (P-E) loops having remnant polarization (2 Pr) around 12.94 µC/cm2 at room temperature. In addition, low temperature P-E measurements show a decrease in Pmax and 2 Pr, which is attributed to the stabilization of defect dipole complexes and domain pinning, as seen in bismuth-based ferroelectrics. Additionally, this decrease in polarization is accompanied by an increase in imprint, confirming the presence of defect dipoles manifested as internal fields. [ABSTRACT FROM AUTHOR]

In this review we concentrate on the work of K. Alex Müller in connection with his activities on oxide perovskites and ferroelectrics which were central to his research career long before he successfully discovered the first high temperature superconductor (HTSC) together with J. G. Bednorz in 1986. Not accidentally, but taking his long experience in perovskite ferroelectrics into account, the first HTSC was an oxide perovskite which had never been considered before to be superconducting. [ABSTRACT FROM AUTHOR]

Structural transition, tetragonality, and dielectric properties are investigated along with thermal and compositional expansion of lead strontium titanate in order to reveal composition dependence and structure-property relation of the ferroelectric structure. Based on the available structural and dielectric data, dielectric stiffness and temperature-dependent paraelectric cubic lattice parameters are analyzed. Non-zero sixth-order free energy coefficients are derived for strontium titanate. Spontaneous polarization, spontaneous strain, volumetric change, and dielectric permittivity are modeled as a function of composition, and the theoretical results are in agreement with experimental data reported in the literature and reveal solid solution effect. [ABSTRACT FROM AUTHOR]

NSFD-2021 included 10 plenaries, 18 invited talks, 30 oral presentations, 88 posters, and a one day workshop for young Researchers with five tutorial sessions on advanced characterization tools for ferroelectric and dielectric materials. The Seminar was divided into 13 sessions and covered a broad range of topics, including the Fundamental of Dielectrics, Ferroelectrics and Related Materials (20%); Materials Design and Processing (30%); Characterization of Polar Materials (3%); Applications of Ferroelectrics and Dielectrics (25%); and, Theoretical Modeling in Dielectrics (10%). The "National Seminar on Ferroelectrics and Dielectrics" biennial dielectrics conference, initiated by the Dielectrics and Ferroelectrics group in India in 1980, has completed 40 years since its humble beginning at the Indian Institute of Technology Delhi. [Extracted from the article]