Comparison of polarization switching in ferroelectric TGS and relaxor SBN crystals

Abstract

The comparative experimental analysis of polarization reversal kinetics in conventional homogeneous triglycine sulfate ((NH 2 CH 2 COOH) 3 ·H 2 SO 4 ; TGS) and relaxor strontium barium niobate (Sr 0.61 Ba 0.39 Nb 2 O 6 ; SBN) crystals have been performed in a broad range of measurement conditions. The experimental data have been collected from microscopic observation of the domain structure, switching current and D −E hysteresis loop registration.The hysteresis loop and dielectric spectra have a strong link to the configuration of ferroelectric microdomains. The domain structure dynamics was examined by the nematic liquid crystal (NLC) method.

Analytical properties of switching current transients in ferroelectrics

“…The analytical Landau-Devonshire theory is used to carry out modeling work involving bipolar square wave electrical pulses. The features of the switching current transients that are generated analytically by varying the temperature and amplitude of the square wave electric pulses in this work reproduce the trends of switching current transients that have been reported experimentally [16,42,46,47,71,79]. A possible application of this work is to model switching current transients involving memory devices such as NVFRAMs [11,78] analytically.…”

“…Comparison with theoretical reports from other groups also show that this work produces similar trends to the switching current profiles obtained previously using bipolar electric pulses with the Landau-Devonshire model [61], the SPICE program [80] for ferroelectric capacitor switching and the Weiss model [40]. With respect to switched polarization, the graphs that have been generated theoretically using equation (14) in figures 11 and 12 reproduce trends that have been reported in experiments involving homogeneous switching of lead zirconate ferroelectric capacitors [47], ultrathin films of copolymer vinylidene-fluoride trifluoroethylene [21,49] and triglycine sulfate crystals [79].…”

“…The theoretically generated switching current transients of this work display the same trend as experimentally reported switching currents of lead zirconate (PZT) thin films [16,17], triglycine sulfate crystals [79], (CH 3 NH 3 ) 5 Bi 2 Br 11 (MAPBB) single crystal [71], Bi 0.9 Li 0.1 FeO 3 (BLFO) thin films [76] and copolymer vinylidene-fluoride trifluoroethylene films [45,46]. Comparison with theoretical reports from other groups also show that this work produces similar trends to the switching current profiles obtained previously using bipolar electric pulses with the Landau-Devonshire model [61], the SPICE program [80] for ferroelectric capacitor switching and the Weiss model [40].…”