Related papers: Macroscopic polarization from nonlinear gradient c…
We analyze the pressure and density equations of state of unpolarized non-relativistic fermions at finite temperature in one spatial dimension. For attractively interacting regimes, we perform a third-order lattice perturbation theory…
We report NdCrTiO5 to be an unusual multiferroic material with large magnetic field dependent electric polarization. While magneto-electric coupling in this two magnetic sub-lattice oxide is well established, the purpose of this study is to…
We systematically investigate the ground-state and the spectral properties of antiferromagnets on a kagom\'{e} lattice with several common types of the planar anisotropy: $XXZ$, single-ion, and out-of-plane Dzyaloshinskii-Moriya. Our main…
The recent discovery of ferroelectric nematic liquid crystalline phases marks a major breakthrough in soft matter research. An intermediate phase, often observed between the nonpolar and the ferroelectric nematic phase, shows a distinct…
Altermagnetism, an emergent magnetic phase featuring compensated collinear magnetic moments and momentum-dependent spin splittings, has recently garnered widespread interest. A critical issue concerns whether the unconventional spin…
Contrary to canonical expectations we show that lattice translational symmetry breaking often accompanies uniformly ordered flux phases. We demonstrate this phenomena by studying a spinless-fermion model on a square latttice with…
The macroscopic dielectric permittivity of dielectric crystals is related to the microscopic atomic polarizability of constituent atoms by the known Clausius-Mossotti relation obtained in the middle of 19th century. We derive a similar…
Interactions between the different degrees of freedom form the basis of many manifestations of intriguing physics in condensed matter. In this respect, quantifying the dynamics of normal modes that themselves arise from these interactions…
We study the interplay of structural and polar distortions in hexagonal YMnO3 and short-period PbTiO3/SrTiO3 superlattices by means of first-principles calculations at constrained electric displacement field D. We find that in YMnO3 the…
Magnetoelectric responses are a fundamental characteristic of materials that break time-reversal and inversion symmetries (notably multiferroics) and, remarkably, of "topological insulators" in which those symmetries are unbroken. Previous…
Spontaneous polarization is essential for ferroelectric functionality in non-centrosymmetric crystals. High-integration-density ferroelectric devices require the stabilization of ferroelectric polarization in small volumes. Here,…
Electrical control of magnetization or magnetic control of polarization offers an extra degree of freedom in materials possessing both electric and magnetic dipole moments viz., magnetoelectric multiferroics. Microstructure with…
Perovskites with tunable and switchable polarization hold immense promise for unlocking novel functionalities. Using density-functional theory, we reveal that intrinsic defects can induce, enhance, and control polarization in…
We present the derivation and code implementation of a first-principles methodology to calculate the lattice-mediated contributions to the bulk flexoelectric tensor. The approach is based on our recent analytical long-wavelength extension…
We develop a general theory of electric polarization induced by inhomogeneity in crystals. We show that contributions to polarization can be classified in powers of the gradient of the order parameter. The zeroth order contribution reduces…
We analyze the phases of an S=1/2 spin model on a lattice of coupled tetrahedra. The presence of both Heisenberg and antisymmetric, Dzyaloshinsky-Moriya interactions can lead to two types of symmetry-broken states: non-magnetic dimer order…
Magnetoelectrics often possess ions located in noncentrosymmetric surroundings. Based on this fact we suggest a microscopic model of magnetoelectric interaction and show that the spin-orbit coupling leads to spin-dependent electric dipole…
We theoretically propose a realization of a nonlinear nonreciprocal transport in antiferromagnets without relying on the relativistic spin-orbit coupling. Through the symmetry and microscopic model analyses, we show that a local spin scalar…
Polar nematic liquid crystals are new classes of condensed-matter states where the inversion symmetry common to the traditional apolar nematics is broken. Establishing theoretical descriptions for the novel phase states is an urgent task.…
We report the formation of a $\mathbb{Z}_2$ vortex crystal in the tetrahedral antiferromagnetic order on a triangular lattice. The noncoplanar tetrahedral state consists of four sublattices with spins oriented along the faces of a…