Domain state properties of the random-field xy-model system Sr_1-xCa_xTiO₃

Ferroelectric order versus metallicity in Sr1−xCaxTiO3−δ ( x<

“…The latter is naturally expected for a tetragonal-to-orthorhombic transition with opposite expansion anomalies of similar magnitudes along the orthorhombic a and b axes. Note that the ferroelectric polarization is expected to be aligned along one of these orthorhombic axes, as it has been discussed in 13,21,66 . In this context, it is also worth to mention that a tetragonalto-orthorhombic transition increases the number of possible twin domains by a factor of two.…”

Interplay between antiferrodistortive, ferroelectric, and superconducting instabilities inSr1−xCaxTiO3−Lima1, Luz2, Oliveira3 et al. 2015Phys. Rev. B323430View full textAdd to dashboardCite

“…In addition, electric field dependent polarization data in higher fields up to 300 V/mm (Novocontrol HVB1000) were obtained evaluating the non-linear permittivity contributions as described in [26]. Since no special surface etching was done after cutting the samples in order to remove eventual passivated surface-layers [20,21], the absolute values of the of the dielectric measurements should be taken with caution.…”

“…However, infinitesimal calcium substitution generates also an anisotropic strain field [21], which has not been taken into account in these theoretical treatments. Therefore, our case cannot be directly compared to the theoretical predictions for stoichiometric systems.…”

“…This was followed by several studies on the effect of doping by calcium on various physical properties [21][22][23]. One interesting outcome of these studies was the observation of an enhancement in the lowtemperature dielectric constant with Ca doping [20,23].…”

Термооптические и диэлектрические исследования сегнетоэлектрической фазы, индуцированной кальцием, в виртуальном сегнетоэлектрике SrTiO-=SUB=-3-=/SUB=-

“…Допирование небольшим количеством примесей (или изотопное замещение 16 O на 18 O в SrTiO 3 ) с концентрацией выше некоторой критической x с приводит к се-гнетоэлектрическому фазовому переходу [1,[4][5][6][7][8][9][10] 18 O x ) 3 и др.) указывают на сосуществование ближнего и дальнего полярного порядка в индуцированной примесями полярной фазе [4][5][6][7][8][11][12][13][14][15][16][17][18][19][20][21][22]. Однако до настоящего времени экспериментальные данные позволяли сделать только качественное описание сосуществования ближнего и дальнего порядка в сегнетофазе.…”