相关论文: Two-step phase changes in cubic relaxor ferroelect…
We present experimental evidence for a first-order freezing/melting phase transition in a nonequilibrium system -- an oscillated two-dimensional isobaric granular fluid. The steady-state transition occurs between a gas and a crystal and is…
For relaxor-ferroelectrics and relaxor-ferromagnets, Ehrenfest classification of phase transitions based on the discontinuity of entropy or specific heat etc. with temperature (T) gives no transition that contradicts the measured order…
We investigate the relaxation of two collective spins in double domain system, which are individually coupled to a single bosonic reservoir, by varying the total number of spins in each domain and their initial spin configurations. A…
Investigating the initial conditions that lead many-body quantum systems to an out-of-equilibrium state is fundamental for understanding their thermalization dynamics. In this work we observe the relaxation for two regimes of excitation…
Local inhomogeneities known as polar nanoregions (PNR) play a key role in governing the dielectric properties of relaxor ferroelectrics - a special class of material that exhibits an enormous electromechanical response and is easily…
We show using extensive simulation results and physical arguments that an Ising system on a two dimensional square lattice, having interactions of random sign between first neighbors and ferromagnetic interactions between second neighbors,…
Phase diagram of solid solutions of antiferroelectric and ferroelectric materials like PbZr$_{1-x}$Ti$_x$O$_3$ (PZT), Rb$_x$(NH$_4$)$_{1-x}$H$_2$PO$% _4$ (RADP) is calculated at the region $x\leq 0.1$. Antiferroelectric and ferroelectric…
We study a dynamic model of relaxor ferroelectrics based on the spherical random-bond---random-field model and the Langevin equations of motion. The solution to these equations is obtained in the long-time limit where the system reaches an…
Ferroelectrics are attractive candidate materials for environmentally friendly solid state refrigeration free of greenhouse gases. Their thermal response upon variations of external electric fields is largest in the vicinity of their phase…
In the studied crystals of FeSe0.7 Te0.3 , a structural phase transition occurs in two stages. At higher temperatures, the electronic subsystem undergoes a reconstruction, leading to a significant increase in elastoresistance. 77 Se NMR…
We discuss ferroelectric phase transitions into single- and multidomain states in very thin films using continuous theory. It is shown that in nearly cubic ferroelectrics the domain state may survive down to atomic film thicknesses, unlike…
Neutron scattering techniques have been used to study the relaxor ferroelectric 0.68PbMg1/3Nb2/3O3-0.32PbTiO3 denoted in this paper as 0.68PMN-0.32PT. On cooling, these relaxor ferroelectrics have a long-range ordered ferroelectric phase…
We present the ground state wave functions for systems of one-dimensional interacting fermions. It is shown that these systems undergo phase transitions similar to the Kosterlitz-Thouless one independently of the interaction details. In the…
We evaluate the charge and longitudinal spin response functions of a two-dimensional electron gas with $e^2/r$ interactions in an arbitrary state of spin polarization, using a structurally self-consistent approach to treat exchange and…
The character of the ground state of an antiferromagnetic insulator is fundamentally altered upon addition of even a small amount of charge. The added charges agglomerate along domain walls at which the spin correlations, which may or may…
All phase transitions can be categorised into two different types: continuous and discontinuous phase transitions. Discontinuous phase transitions are normally accompanied with significant structural changes, and nearly all of them have the…
The pressure-temperature phase diagram of a one-component system, with particles interacting through a spherically symmetric pair potential in two dimensions is studied. The interaction consists of a hard core plus an additional repulsion…
The dynamics of weak vs. strong first order phase transitions is investigated numerically for 2+1 dimensional scalar field models. It is argued that the change from a weak to a strong transition is itself a (second order) phase transition,…
New field content beyond that of the Standard Model of particle physics can alter the thermal history of electroweak symmetry breaking in the early universe. In particular, the symmetry breaking may have occurred through a sequence of…
An improved thermodynamic cycle is proposed, where the cooling effect of an electrocaloric refrigerant is enhanced by applying a reversed electric field. In contrast to conventional adiabatic heating or cooling by on-off cycles of the…