Granular structure and dielectric characteristics of the (Ba0.5Sr0.5)Nb2O6 ceramics

Phenomenological theory of uniaxial relaxor ferroelectrics

“…The resulting cumbersome expression is not shown here. All coefficients of the potential (1) listed in table 1 were found from experimental hysteresis loops of BSN ceramics samples [24] using least-squares data treatment. Linear temperature dependence was assumed for the coefficients of the second-order terms in equation (1).…”

“…The hysteresis loops calculated from the thermodynamic potential (1) with the coefficients listed in table 1 are presented in figure 2, where blue curves correspond to P − E loops and red to ξ − E loops. Experimental points obtained in [24] for BSN50 are shown at selected temperatures (298 K, 333 K and 378 K). There is good agreement between our calcul ations and experimental data.…”

“…Figure 2. Temperature dependences of susceptibility (black line) calculated according to equation (3), inversed squared frequency of the soft mode (blue line), experimental data (open symbols)[24] are presented in the middle panel. Environing panels show the hysteresis loops for BNS50 relaxor.…”

“…Full symbols on the susceptibility curve correspond to particular temperatures for which the hysteresis P − E loops (blue) and ξ − E loops (red) were calculated. Experimental hysteresis loops (small open symbols) from[24] are shown at selected temperatures (298 K, 333 K and 378 K). Note that ξ − E loops were not normalized.…”

Phase transformations in barium-strontium niobate SBN-50 in the temperature range from 80 K to 700 K according to Raman spectroscopy data

“…The partial filling of channels in a real SBN structure results in disordering, which is a source of many unusual properties [2]. Some SS of SBN have high electrooptic coefficients, photorefractive effect [3], as well as significant pyroelectric and piezoelectric properties [4][5][6] that make them promising materials for application in modern functional microelectronics and optoelectronic devices [7]. Despite the extensive studying of barium strontium niobates for more than 50 years, currently the issues related to understanding the nature of relaxor properties manifestation, mechanisms of spontaneous polarization emergence and phase transformations in them remain pending.…”