Related papers: Unconventional Multiferroicity in Cupric Oxide
We have measured the magnetization and specific heat of multiferroic CoCr2O4 in magnetic fields up to 14 T. The high-field magnetization measurements indicate a new phase transition at T* = 5 - 6 K. The phase between T* and the lock-in…
The sequence of phase transitions and the symmetry of in particular the low temperature incommensurate and spin-Peierls phases of the quasi one-dimensional inorganic spin-Peierls system TiOX (TiOBr and TiOCl) have been studied using…
We investigate the spin-induced polarization in the multiferroic compound Ba2CuGe2O7 using variarional and finite temperature mean field approaches. The compound is described by a spin-3/2 Heisenberg model extended with easy plane…
Through a combination of neutron diffraction and Landau theory we describe the spin ordering in the ground state of the quadruple perovskite manganite CaMn7O12 - a magnetic multiferroic supporting an incommensurate orbital density wave that…
I consider skyrmionic states in non-centrosymmetric magnets near the ordering temperatures. I show that the interaction between the chiral skyrmions, being repulsive in a broad temperature range, changes into attraction at high…
When considering magnetic systems in the thermodynamic limit and at low enough temperature, one finds typically magnetically ordered phases. In contrast, in the high-temperature regime, the interactions between the spin degrees of freedom…
The behavior in an external magnetic field is studied for a wide class of multichain quantum spin models. It is shown that the magnetic field together with the interchain couplings cause commensurate-incommensurate phase transitions between…
We studied phase transitions and thermodynamic properties of the field-induced antiferromagnetic nuclear-spin ordered phase in bcc solid 3He by measuring the melting pressure at temperatures down to 0.4 mK in magnetic fields up to 15 T. The…
The magnetic and multiferroic phase diagram of Mn$_{0.85}$Co$_{0.15}$WO$_4$ single crystals is investigated by means of magnetic, heat capacity, dielectric, polarization, and neutron scattering experiments. Three magnetic phase transitions…
In many materials, ordered phases and their order parameters are easily characterized by standard experimental methods. "Hidden order" refers to a phase transition in which an ordered state emerges without such an easily detectable order…
High pressure neutron diffraction is employed to investigate the magnetic behavior of CaMn$_2$Bi$_2$ in extreme conditions. In contrast to antiferromagnetic ordering on Mn atoms reported at ambient pressure, our results reveal that at high…
To study the relationship between the properties of low-dimensional spin systems with weakly coupled Cu-triangles and their crystal structure, single crystals of $Cs_3Cu_3Cl_8OH$ (1) and the new $Cs_3Cu_3Cl_{7.6}Br_{0.4}OH$ (2) were grown.…
We report on a detailed single crystal x-ray diffraction study of the unconventional spin-Peierls compound TiOCl. The intermediate phase of TiOCl is characterized by an incommensurate modulation which is virtually identical to that recently…
The copper-oxide based high temperature superconductors have complex phase diagrams with multiple ordered phases. It even appears that the highest superconducting transition temperatures for certain cuprates are found in samples which…
The geometrically frustrated magnet Ni3V2O8 undergoes a series of competing magnetic ordering at low temperatures. Most importantly, one of the incommensurate phases has been reported to develop a ferroelectric correlation caused by spin…
The crystal structure of the double tungstate NaFe(WO$_4$)$_2$ arises from that of the spin-driven multiferroic MnWO$_4$ by inserting non-magnetic Na layers. NaFe(WO$_4$)$_2$ exhibits a three-dimensional incommensurate spin-spiral structure…
We have successfully synthesized three quasi-2D geometrically frustrated magnetic compounds (\alpha-MCr_2O_4, M=Ca, Sr, Ba) using the spark-plasma-sintering technique. All these members of the \alpha-MCr_2O_4 family consist of the stacking…
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…
We have investigated the magnetic ground-state of the multiferroic relaxor ferroelectric \pfn with $\mu$SR spectroscopy and neutron scattering. We find that a transition to a partially disordered phase occurs below T=20 K that coexists with…
Type-II multiferroics, where spin interactions induce a ferroelectric polarization, are interesting for new device functionalities due to large magnetoelectric coupling. We report on a new type of multiferroicity in the quadruple-perovskite…