相关论文: Ferroelectricity in Incommensurate Magnets

We focus on a broad class of tetragonal itinerant systems sharing a tendency towards the spontaneous formation of incommensurate magnetism with ordering wavevectors $\mathbf{Q}_{1,2}=(\pi-\delta,0)/(0,\pi-\delta)$ or…

We present the microscopic theory of improper multiferroicity in BiMnO3, which can be summarized as follows: (1) the ferroelectric polarization is driven by the hidden antiferromagnetic order in the otherwise centrosymmetric C2/c structure;…

The family of molecular conductors TMTTF/TMTSF-X demonstrates almost all known electronic phases in parallel with a set of weak structural modifications of anion ordering and mysterious structureless transitions. Only in early 2000's their…

Ferroelectricity has been one major focus in modern fundamental research and technological application. We consider the physical origin of improper ferroelectricity in Mott insulating materials. Beyond the well-known…

This letter addresses basic questions concerning ferroelectric order in positionally disordered dipolar materials. Three models distinguished by dipole vectors which have one, two or three components are studied by computer simulation.…

General microscopic mechanism of ferroelectric ordering in chiral smectic C* liquid crystals is considered. It is shown that if the mesogenic molecules have a sufficiently low symmetry, the spontaneous polarization is proportional to one of…

We clarify that the antiferromagnetic order in the distorted tetrahedral quasi-one dimensional spin system induces electric polarizations. In this system, the effects of the low dimensionality and the magnetic frustration are expected to…

In this contribution to the special issue on magnetoelectrics and their applications, we focus on some single phase multiferroics theoretically predicted and/or experimentally discovered by the authors in recent years. In these materials,…

A theoretical description of the sequence of magnetic phases in Co3TeO6 is presented. The strongly first-order character of the transition to the commensurate multiferroic ground state, induced by coupled order parameters corresponding to…

The generic magnetic phase diagram of multiferroic RMn$_2$O$_5$ (with R=Y, Ho, Tb, Er, Tm), which allows different sequences of ordered magnetic structures for different R's and different control parameters, is described using order…

The effects of high magnetic fields applied perpendicular to the spontaneous ferroelectric polarization on single crystals of BiFeO$_3$ were investigated through magnetization, magnetostriction, and neutron diffraction measurements. The…

It is still under intensive discussion, how magnetoelectric coupling actually occurs at the atomic scale in multiferroic BiFeO3. Nuclear solid-state techniques monitor local fields at the atomic scale. Using such an approach, we show that,…

Magnetoelectric (ME) effect is recognized for its utility for low-power electronic devices.Largest ME coefficients are often associated with phase transitions in which ferroelectricity is induced by magnetic order. Unfortunately, in these…

A material that reveals two or more ferroelectric properties at the same time is called multiferroic materials. The most commonly multiferroic materials shows ferroelectricity and ferromagnetism property within a single phase. Accordingly…

Neutron diffraction and nuclear quadrupole resonance (NQR) measurements were employed to investigate magnetic order in the non-ferroelectric phase preceding the low-temperature multiferroic state in FeTe2O5Br. Refnement of the neutron…

The low-temperature magnetic structure of \HG has been studied by high-resolution powder neutron diffraction. Long-range incommensurate magnetic order sets in at T$_N\sim$22K with propagation vector \textbf{k}=(0,0,$\sim$0.18). On cooling…

Materials with coexisting and coupled ferroelectric and magnetic orders are rare. Here we show, using density functional theory calculations, that inducing Fe$_\mathrm{La}$ antisites into non-ferroelectric and antiferromagnetic LaFeO$_3$…

Magnetic ordering phenomena in CexPr1-xB6 solid solutions have been studied using both powder and single-crystal neutron diffraction. A variety of magnetic structures are observed depending on temperature and Ce concentration. Over a broad…

In this paper, we explore magneteoelectricity of rare earth orthochromites from the symmetry point of view. We determine the principal structural order parameters and find their couplings with ferroelectric and magnetic orderings. Our…

We investigate ferroaxial magnets, a new class of spin-order-driven multiferroic magnets in which magnetic ordering induces mirror-symmetry breaking while preserving both time-reversal and spatial-inversion symmetries. These systems exhibit…