Related papers: First-principles study of Exchange Interaction in …
We have calculated Heisenberg exchange parameters for bcc-Fe, fcc-Co, and fcc-Ni using the scalar-relativistic spin-polarized Green function technique within the tight-binding linear muffin-tin orbital method and by employing the magnetic…
A complex magnetic order of the multiferroic compound Co3TeO6 has been revealed by neutron powder diffraction studies on ceramics and crushed single crystals. The compound adopts a monoclinic structure (s.g. C2/c) in the studied temperature…
We present results of an {\it ab initio} density functional theory study of three bismuth-based multiferroics, BiFeO$_{3}$, Bi$_{2}$FeCrO$_{6}$, and BiCrO$_{3}$. We disuss differences in the crystal and electronic structure of the three…
We study the spin chain behavior, a transition to 3D magnetic order and the magnitudes of the exchange interactions for the metal-amino acid complex Cu(D,L-alanine)2.H2O, a model compound to investigate exchange couplings supported by…
Heat-capacity (C) and ac susceptibility measurements have been performed on the spin-chain compounds, Sr3ZnRhO6 and Ca3NiMnO6, to establish their magnetic behavior and to explore whether there are magnetic frustration effects due to…
The pseudo-one dimensional brannerite type compound CoV2O6 has been studied by magnetisation and heat capacity measurements in the temperature range 1.8 < T < 300 K and in applied fields of up to 9 T. Our measurements show an unusual…
We have investigated multiple caloric effects in multiferroic Y2CoMnO6. Polycrystalline sample prepared by solid state method has shown a ferromagnetic Curie temperature 75 K with second order phase transition; a maximum magneto entropy…
Our measured dielectric constant and mechanical response of multiferroic BiFeO3 indicate four phase transitions below room temperature. Features correlate with those reported at 50K (from a peak in the zero-field-cooled magnetic…
The magnetic behavior of a solid solution, Ca3-xYxCo2O6, based on an exotic spin-chain compound, Ca3Co2O6, crystallizing in K4CdCl6-derived rhombohedral structure is investigated. Among the compositions investigated (x= 0.0, 0.3, 0.5, 0.75…
Dielectric constant measurement under magnetic field is an efficient technique to study the coupling between charges and spins in insulating materials. For magnetic oxides, the geometric frustration is known to be a key ingredient to…
Specific heat measurements were carried out on the closely related spin-chain oxides Ca3Co2O6 and Ca3CoRhO6. Both compounds consist of Ising magnetic chains that are arranged on a triangular lattice. The spin coupling along and between the…
On the basis of density functional theory electronic band structure calculations using the augmented spherical wave method, the electronic and magnetic properties of the orthorhombic and tetragonal phases of Ca3Mn2O7 were investigated and…
We demonstrate the exchange coupling of a ferromagnetic semiconductor (Ga1-xMnxAs) with an overgrown antiferromagnet (MnO). Unlike most conventional exchange biased systems, the blocking temperature of the antiferromagnet (T_B = 48 +- 2 K)…
Geometrically frustrated structures combined with competing exchange interactions that have different magnitudes are known ingredients for achieving exotic properties. Herein, we studied detailed structural, magnetic, thermal (specific…
We use quantum Monte Carlo to determine the magnetic and transport properties of coupled square lattice spin and fermionic planes as a model for a metal-insulator interface. Specifically, layers of Ising spins with an intra-layer exchange…
Two magnetic ordering transitions are found in InMnO3, the paramagnetic to antiferromagnetic transition near ~118 K and a lower possible spin rotation transition near ~42 K. Multiple length scale structural measurements reveal enhanced…
Ca_3Co_{2-x}Mn_xO_6 (x ~ 0.96) is a multiferroic with spin-chains of alternating Co(2+) and Mn(4+) ions. The spin state of Co(2+) remains unresolved, due to a discrepancy between high temperature X-ray absorption (S=3/2) and low temperature…
A combination of magnetic heat capacity measurements versus temperature under multiple fixed external fields using a polycrystalline sample, plus easy and hard axis aligned magnetization versus field measurements using a single crystal of…
Using powder neutron diffraction we have discovered an unusual magnetic order-order transition in the Ising spin chain compound Ca3Co2O6. On lowering the temperature an antiferromagnetic phase with propagation vector k=(0.5,-0.5,1) emerges…
Exchange interactions up to fourth nearest neighbor are shown within a classical local-moment Heisenberg approach to be important to model inelastic neutron scattering data on the fcc kagome antiferromagnet IrMn$_3$. Spin wave frequencies…