Ferroelectric relaxor behaviour in Pb(Fe0.5Ta0.5)O3

Abstract

:The relaxor ferroelectric lead iron tantalate, Pb(Fe 0.5 Ta 0.5 )O 3 (PFT) is synthesized by Coulombite precursor method. The X-ray diffraction pattern of the sample at room temperature shows a cubic phase. The field dependence of dielectric response is measured in a frequency range 0.1 kHz -1 MHz and in a temperature range from 173-373 K. The temperature dependence of permittivity (ε ′) shows broad maxima at various frequencies. The frequency dependence of the permittivity maximum temperature (T m ) has been modelled using Vogel-Fulcher relation.

Electric field dependences of Curie and Néel phase transition temperatures in magnetoelectric relaxor multiferroic Pb(Fe0.5 Ta0.5 )O3 crystals seen via acoustic emission

“…Pb(Fe 0.5 Ta 0.5 )O 3 (PFT) is well‐known to be such a relaxor‐multiferroic . Besides, PFT belongs also to non‐canonical RFEs due to undergoing the structural phase transitions from cubic () phase ( T ≥ T c 1 ≈ 270 K) to a tetragonal ( P4mm ) intermediate phase (270 K ≥ T ≥ 220 K) and then to a low‐temperature monoclinic ( Cm ) phase ( T ≤ T c 2 ≈ 220 K) , and in the same time its T m exhibits the frequency dependence following the Vogel‐Fulcher law . The Fe 3+ and Ta 5+ ions randomly occupy the B‐sites and their ionic charge disorder originates RFs which provoke RFE properties.…”

Room temperature relaxor ferroelectricity and spin glass behavior in Sr2FeTiO6 double perovskite

“…The presence of magneto-electric coupling (ME) in these compounds promises important applications in spintronics devices such as magnetic tunnel junctions or low field magnetoresistive sensors [3]. In addition to their magnetic properties, the giant dielectric constant and the dielectric relaxation are also observed, which have generated considerable interest due to their possible applications in technologies like memory storage devices, micro-electro-mechanical system, multilayer ceramic capacitors and optoelectronic devices [4][5][6][7].…”

Variation of Dielectric and Electrical Properties of Zr-Substituted Lead Calcium Iron Niobate with Temperature and Frequency

“…The temperature of dielectric maxima (T m ) has shifted towards higher temperature with increase in frequency, which is similar to the dielectric relaxation of PFN. 21 The degree of relaxation behavior is described by the parameter DT relaxor , 22,23 and is defined as:…”