We derive novel sufficient conditions for convergence of Loopy Belief Propagation (also known as the Sum-Product algorithm) to a unique fixed point. Our results improve upon previously known conditions. For binary variables with (anti-)ferromagnetic interactions, our conditions seem to be sharp.

We show that in superlattices with alternating superconducting (S) and ferromagnetic (F) layers the spontaneous magnetic field induced due to electromagnetic proximity effect becomes dramatically enhanced compared previously studied S/F bilayers. The reveals itself for in-plane orientation of moments both anti-ferromagnetic ordering F layers. In finite size samples decays from sample surface to...

Abstract Using first-principles calculations, we investigate the magnetic order in two-dimensional (2D) transition-metal-dichalcogenide (TMD) monolayers: MoS 2 , MoSe MoTe WSe and WS substitutionally doped with period four transition-metals (Ti, V, Cr, Mn, Fe, Co, Ni). We uncover five distinct magnetically ordered states among 35 TMD-dopant pairs: non-magnetic (NM), ferromagnetic out-of-plane s...

The Hartree-Fock-RPA approach is applied to the 1D anti-ferromagnetic Heisen-berg model in the Jordan-Wigner representation. Somewhat contrary to expectation , this leads to reasonable results for spectral functions and sum rules in the symmetry unbroken phase. In a preliminary application of Self-Consistent RPA to finite size chains strongly improved results are obtained. The 1D Anti-Ferromagn...

The restricted solid-on-solid models in the anti-ferromagnetic regime is studied in the framework of quantum affine algebras. Following the line developed recently for vertex models, a representation theoretical picture is presented for the structure of the space of states. The local operators and the creation/annihilation operators of quasi-particles are defined using vertex operators, and the...

The Bethe ansatz equations for the spin 1/2 Heisenberg XXZ spin chain are numerically solved, and the energy eigenvalues are determined for the anti-ferromagnetic case. We examine the relation between the XXZ spin chain and the Thirring model, and show that the spectrum of the XXZ spin chain is different from that of the regularized Thirring model.

The synthesis and structural characterisation of three small nickel(II) cages are reported, all stabilised by pivalate ligands. The magnetic properties of the cages have been studied by a combination of susceptibility measurements and inelastic neutron scattering. For a dinuclear cage, [Ni2(mu-OH2)(O2CCMe3)4(HO2CCMe3)4] 1 the ground state is S=2, with a ferromagnetic exchange interaction betwee...