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Many perovskite materials experience a temperature-driven phase transition at the Curie temperature from a non-centrosymmetric polar ferroelectric phase to a paraelectric phase, where polarization is lost. The paraelectric phase is usually centrosymmetric ...
Bloch theorem is useful for analyzing wave propagation in periodic systems. It has been widely used to determine the energy bands of various translationally-periodic crystals and with the advent of nanoscale structures like nanotubes, it has been extended ...
Vibrational properties of molecular crystals are constantly used as structural fingerprints, in order to identify both the chemical nature and the structural arrangement of molecules. The simulation of these properties is typically very costly, especially ...
The symmetry theory of halving objects into two identical fragments is developed and illustrated by examples. La coupe du roi is a fascinating way to slice an apple into chiral fragments with the same handedness. It may be applied to any object with point ...
We use the coset construction of low-energy effective actions to systematically derive Wess-Zumino (WZ) terms for fluid and isotropic solid systems in two, three, and four spacetime dimensions. We recover the known WZ term for fluids in two dimensions as w ...
Metallic nanoclusters form a family of novel materials with atomically defined hybrid organic/inorganic structures. Among these materials, clusters containing 44 silver atoms have emerged as one of the most interesting, because of their exceptional electro ...
Short- and long-range impurity-induced polar ordering in Sr1-xCaxTiO3 (x = 0.014) single crystals was investigated and discussed on the basis of light refraction, morphic birefringence and temperature-dependent dielectric hysteresis loop measurements. Anew ...
Cellular checkerboard patterns are observed at many stages of embryonic development. We study an analytically tractable model for lateral inhibition and show that the steady states are analogous to optical phonons at the Gamma point, which have the wave nu ...
The charged domain wall is an ultrathin (typically nanosized) interface between two domains; it carries bound charge owing to a change of normal component of spontaneous polarization on crossing the wall. In contrast to hetero-interfaces between different ...
The expressions for the spontaneous polar contribution delta n (i) (s) to the principal values of the refractive index due to the quadratic electro-optic effect in ferroelectrics have been considered within the phenomenological approach taking into account ...
