A study of the magnetocaloric properties of manganites with ferromagnetic and chargeordering states is presented. Under the application of a magnetic field in the vicinity of the paramagnetic-ferromagnetic and paramagnetic-charge order transitions large changes of the magnetic entropy are found, negative or positive, respectively. The physical mechanisms that contribute to the magnetic entropy ...

A possible mechanism for a ferromagnetic interaction in the rhombic (Rh) form of C60 (Rh-C60) is suggested on the basis of theoretical studies in relation to cage distortion of the C60 unit in the polymerized 2D-plane. Band structure calculations on Rh-C60 show that cage distortion leads to competition between diamagnetic and ferromagnetic states,which give rise to the possibility of thermally ...

Spin dynamics in the generalized ferromagnetic Kondo model for manganites. Dynamical spin susceptibility is calculated for the generalized ferromagnetic Kondo model which describes itinerant e g electrons interacting with localized t 2g electrons with antiferromagnetic coupling. The calculations done in the mean field approximation show that the spin-wave spectrum of the system in ferromagnetic...

We predict a spin echo in electron transport through layered ferromagnetic-normal-ferromagnetic metal structures: whereas a spin current polarized perpendicular to the magnetization direction decays when traversing a single homogeneous ferromagnet on the scale of the ferromagnetic spin-coherence length, it partially reappears by adding a second identical but antiparallel ferromagnet. This reent...

Ferromagnetism is used to characterize magnetic behavior of a material, such as the strong attraction to a permanent magnet. The origin of this strong magnetism is the presence of a spontaneous magnetization which is produced by a parallel alignment of spins. Instead of a parallel alignment of all the spins, there can be an anti-parallel alignment of unequal spins. This results in a spontaneous...

Ferromagnetic metal rings of nanometre range widths and thicknesses exhibit fundamentally new spin states, switching behaviour and spin dynamics, which can be precisely controlled via geometry, material composition and applied f eld. Following the discovery of the ‘onion state’, which mediates the switching to and between vortex states, a range of fascinating phenomena has been found in these s...

geometrically nonlinear governing equations for a plate with linear viscoelastic material are derived. the material model is of boltzmann superposi¬tion principle type. a third-order displacement field is used to model the shear deformation effects. for the solution of the nonlinear governing equations the dynamic relaxation (dr) iterative method together with the finite difference discretizati...

The non-magnetic and non-Fermi-liquid CaRuO3 is the iso-structural analog of the ferromagnetic (FM) and Fermi-liquid SrRuO3. We show that an FM order in the orthorhombic CaRuO3 can be established by the means of tensile epitaxial strain. The structural and magnetic property correlations in the CaRuO3 films formed on SrTiO3 (100) substrate establish a scaling relation between the FM moment and t...

Theoretical description of the ferromagnetic π-junctions near the critical temperature Abstract The theory of ferromagnetic π-junction near the critical temperature is presented. It is demonstrated that in the dirty limit the modified Usadel equation adequately describes the proximity effect in ferromagnets. To provide the description of an experimentally relevant situation, oscillations of the...

We compute the phase diagram of a biased graphene bilayer. The existence of a ferromagnetic phase is discussed with respect to both carrier density and temperature. We find that the ferromagnetic transition is first-order, lowering the value of U relatively to the usual Stoner criterion. We show that in the ferromagnetic phase the two planes have unequal magnetization and that the electronic de...