相关论文: The Symmetry of Multiferroics

We investigate the appearance of an inversion-asymmetric antiferromagnetism due to an itinerant mechanism in nonsymmorphic systems with magnetic ions at Wyckoff position of multiplicity 2. The key symmetries which underpin the existence of…

Ferroelectric and ferromagnetic materials possess spontaneous electric and magnetic order, respectively, which can be switched by the corresponding applied electric and magnetic fields. Multiferroics combine these properties in a single…

We show that time-reversal symmetry broken, centrosymmetric antiferromagnets with nonrelativistic spin-splitting are conveniently described in terms of the ferroic ordering of magnetic octupoles. The magnetic octupoles are the lowest-order…

We investigate a three component fermion mixture in the presence of weak attractive interactions. We use a combination of the equation of motion and the Gaussian variational mean-field approaches, which both allow for simultaneous…

We discuss a model scenario for multiferroic systems of type II (collinear spins) where the electric dipolar order competes with a frustrated magnetic order in determining the elastic distortions of the lattice ion positions. High magnetic…

Materials that combine magnetic and ferroelectric properties have generated increasing interest over the last few years, due to both their diverse properties and their potential utility in new types of magnetoelectric device applications.…

We report the development of a hybrid numerical / analytical model capable of mapping the spatially-varying distributions of the local ferromagnetic resonance (FMR) frequency and dynamic magnetic susceptibility in a wide class of patterned…

Magnetic toroidal order features a loop-like arrangement of magnetic dipole moments, thus breaking both spatial inversion (P) and time-reversal (T) symmetries while preserving their combined PT sym-metry. This PT symmetry enables a linear…

In this contribution we would like to revisit the problems of ferromagnetism (F) and antiferromagnetism (AF) in the pure itinerant model. These methods can be extended later to the superconducting materials. In our model we assume the…

Magnetic, dielectric and calorimetric studies on 0.9BiFeO3-0.1BaTiO3 indicate strong magnetoelectric coupling. XRD studies reveal a very remarkable change in the rhombohedral distortion angle and a significant shift in the atomic positions…

In a collinear magnet, the predominant magnetic moments are collectively aligned along a specific spatial orientation, and this alignment may yield intriguing phenomena such as spin orientation driven polarization. It is well known that…

Control and detection of spin order in ferromagnets is the main principle allowing storing and reading of magnetic information in nowadays technology. The large class of antiferromagnets, on the other hand, is less utilized, despite its…

Phases that go beyond dipolar ordering and into multipolar ordering have recently been observed in magneto-electric materials. The resulting phase diagram is commonly explained using the concept of competing orders and exact microscopic…

The deterministic switching of magnetic order parameters is critically important, as it forms the fundamental basis for manipulating information states in magnetic memory devices. This work presents a general theoretical framework that…

Magnetic Compton scattering is an established tool for probing magnetism in ferromagnetic or ferrimagnetic materials with a net spin polarization. Here we show that, counterintuitively, {\it non-magnetic} systems can also have a non-zero…

We have carried out 63,65Cu NMR spectra measurements in magnetic field up to about 15.5 T on single crystal of a multiferroic triangular-lattice antiferromagnet CuCrO2. The measurements were performed for perpendicular and parallel…

A phase transition is often accompanied by the appearance of an order parameter and symmetry breaking. Certain magnetic materials exhibit exotic hidden-order phases, in which the order parameters are not directly accessible to conventional…

We present a simple two-dimensional model in which the lattice degrees of freedom mediate the interactions between magnetic moments and electric dipoles. This model reproduces basic features, such as a sudden electric polarization…

We investigate the possible types of coupling between ferroelectricity and magnetism for the zig-zag spin chain multiferroic LiCu2O2 compound. We construct a multi-order parameter phenomenological model for the material based on a group…

Magnetoelectric multiferroic materials, particularly with the perovskite structure, are receiving a lot of attention because of their inherent coupling between electrical polarization and magnetic ordering. However, very few types of direct…