相关论文: Long Range orders in multiferroics

The ferroelectricity of multiferroics induced by spin order is commonly explained by considering either purely electronic or ion-displacement contribution. However, there is no general model which includes both effects simultaneously. Here,…

Recent experiments show that charge-density-wave correlations are prevalent in underdoped cuprate superconductors. The correlations are short ranged at weak magnetic fields but their intensity and spatial extent increase rapidly at low…

Multiferroics are materials with coexisting electric and magnetic orders that are of central importance for fundamental research and technological applications. Unfortunately, intrinsic multiferroics that operate at room temperature remain…

Multiferroics are compounds in which at least two ferroic orders coexist - typically (anti)ferromagnetism and ferroelectricity. While magnetic order can arise in both insulating and conducting compounds, ferroelectricity is in principle not…

Type-II multiferroics, where spin order induces ferroelectricity, exhibit strong magnetoelectric coupling. However, for the typical 2D type-II multiferroic NiI$_2$, the underlying magnetoelectric mechanism remains unclear. Here, applying…

Using density functional theory calculations, ultrathin films of SrVO3(d1) and SrCrO3(d2) on SrTiO3 substrates have been studied as possible multiferroics. Although both are metallic in the bulk limit, they are found to be insulating as a…

We formulate measures of spin ordering in the $q$-state ferromagnetic Potts model in a generalized external magnetic field that favors or disfavors spin values in a subset $I_s = \{1,...,s\}$ of the total set of $q$ values. The results are…

Since its discovery a decade ago, "polar metallic phase" has ignited significant research interest, as it further functionalizes the switchable electric polarization of materials with additional transport capability, granting them great…

Effects of geometrical frustration and quantum fluctuation are theoretically investigated for the proton ordering in a quasi-two-dimensional hydrogen-bonded system, squaric acid crystal. We elucidate the phase diagram for an effective…

CuFeO_2 is one of the multiferroic materials and is the first case that the electric polarization is not explained by the magnetostriction model or the spin-current model. We have studied this material using soft x-ray resonant diffraction…

Orbital angular momentum and torque transfer play central roles in a wide range of magnetic textures and devices including skyrmions and spin-torque electronics(1-4). Analogous topological structures are now also being explored in…

The theoretical merits of longitudinal polarization asymmetries of electron-positron annihilation into two final fermions at future colliders are examined, using a recently proposed theoretical description. A number of interesting features,…

This thesis deals with the Hubbard model as prototypical model to describe the physics of electrons in the two-dimensional copper-oxide planes of high-$T_c$ cuprates. To get approximate solutions, we employ functional renormalization group…

The wave equation for spinless particles with the Lorentz violating term is considered. We formulate the third-order in derivatives wave equation leading to the modified dispersion relation. The first-order formalism is considered and the…

A high-order extension is presented for the electromagnetic gyrokinetic formulation in which the parallel canonical momentum is taken as one of phase space coordinates. The high-order displacement vector associated with the guiding-center…

Neutron diffraction measurements on multiferroic LuFe2O4 show changes in the antiferromagnetic (AFM) structure characterized by wavevector q = (1/3 1/3 1/2) as a function of electric field cooling procedures. The increase of intensity from…

We study formation of the charge-density wave long-range order in a system of repulsive 1D electrons coupled to 3D phonons. We show that the CDW can be stabilized by interaction with phonons in quasi-1D crystals and semiconducting…

Electron localization is the tendency of an electron in a many-body system to exclude other electrons from its vicinity. Using a new natural measure of localization based on the exact manyelectron wavefunction, we find that localization can…

We predict high-order harmonics in which the polarization within the spectral bandwidth of each harmonic varies continuously and significantly. For example, the interaction of counter-rotating circularly-polarized bichromatic drivers having…

Multiferroics, materials where spontaneous long-range magnetic and dipolar orders coexist, represent an attractive class of compounds, which combine rich and fascinating fundamental physics with a technologically appealing potential for…