相关论文: Paraelectric in a Strong High-Frequency Field
The phase diagram of a quantum paraelectric antiferromagnet EuTiO3 under an external electric field was calculated using Landau-Ginzburg-Devonshire theory. It was shown that the application of an external electric field E leads to the…
Using first-principles calculations, we estimated the impact of large applied electric E fields on the structural, dielectric, and ferroelectric properties of typical ferroelectrics. At large fields, the structural parameters change…
We investigate numerically the homogenized permittivities of composites made of low index dielectric inclusions in a ferroelectric matrix under a static electric field. A refined model is used to take into account the coupling between the…
Understanding collective phenomena in quantum materials from first principles is a promising route toward engineering materials properties on demand and designing new functionalities. This work examines the quantum paraelectric state, an…
Measurements of the low-frequency (f<=100 kHz) permittivity and conductivity at T<= 150 K are reported for La(1-x)Ca(x)MnO(3) (0<=x<=1) and Ca(1-y)Sr(y)MnO(3) (0<=y<=0.75) having antiferromagnetic, insulating ground states covering a broad…
Monte Carlo simulations have been used to study a discretized Heisenberg ferromagnet (FM) in a random field on simple cubic lattices. The spin variable on each site is chosen from the twelve [110] directions. The random field has infinite…
Thin films of the manganite (La$_{1-y}$Pr$_y$)$_{1-x}$Ca$_x$MnO$_3$ exhibit dynamic phase coexistence with micrometer scale, fluid-like ferromagnetic metallic (FMM) regions interspersed in a charge-order insulating (COI) background. It has…
Recent observations of unusual ferroelectricity in thin films of HfO_2 and related materials have attracted broad interest to the materials and led to the emergence of a number of competing models for observed behaviors. Here we develop the…
Pb_1.83Mg_0.29Nb_1.71O_6.39 (PMN) crystallizing in a cubic pyrochlore structure exhibits, as the first dielectrics with pyrochlore structure, typical feature of quantum paraelectrics - its permittivity continuously increases on cooling and…
The structural phase transition in hexagonal BaMnO$_3$ occurring at $T_c$=130 K was studied in ceramic samples using electron and X-ray diffraction, second harmonic generation as well as by dielectric and lattice dynamic spectroscopies. The…
Inertial magnetization dynamics have been predicted at ultrahigh speeds, or frequencies approaching the energy relaxation scale of electrons, in ferromagnetic metals. Here we identify inertial terms to magnetization dynamics in thin…
Thermoelectric power measurements on the heavy fermion antiferromagnet Ce(Ru0.92Rh0.08)2Si2 under magnetic field (H) show clearly that the antiferromagnetic state below the critical field Hc ~ 2.8T can be fully decoupled from the…
A systematic study of thermomagnetic irreversibility CoS$_{1.76}$Se$_{0.24}$ has been carried out. Our study shows that the resistivity at low temperature can be tuned by cooling in different magnetic fields and the critical field required…
We use different types of determinantal Hartree-Fock (HF) wave functions to calculate variational bounds for the ground state energy of spin-half fermions in volume V_0, with mass m, electric charge zero, and magnetic moment mu, which are…
High Seebeck coefficient by creating large density of state (DOS) around the Fermi level through either electronic structure modification or manipulating nanostructures, is commonly considered as a route to advanced thermoelectrics.…
We present a method for extracting high-spatial resolution dielectric constant data at microwave frequencies. A scanning near field microwave microscope probes a sample and acquires data in the form of the frequency and quality factor…
A novel nonlinear effect of anomalously deep penetration of an external radio frequency electric field into a plasma is discribed. A self-consistent kinetic treatment reveals a transition region between the sheath and the plasma. Because of…
It is shown that a sufficiently strong external electric field causes a decrease in the transition temperature of ferroelectric, antiferroelectric, and metal-insulator transitions. The temperature dependence of the critical electric field…
We consider a finite Fermi-system where the residual interactions create a soft mode of the excitation spectrum. Because of the large vibrational amplitude, the standard random phase approximation does not work in this situation. We develop…
Much attention has been given recently to flexible and wearable integrated-electronic devices, with a strong emphasis on real-time sensing, computing and communication technologies. Thin ferroelectric films exhibit switchable polarization…