Related papers: Multipolar exchange interaction and complex order …
We study the two dimensional quantum Heisenberg antiferromagnet on the square lattice with easy-axis exchange anisotropy. By the semiclassical method called pure-quantum self-consistent harmonic approximation we analyse several…
We examine the magnetic phase diagram of iron pnictides using a five band model. For the intermediate values of the interaction expected to hold in the iron pnictides, we find a metallic low moment state characterized by antiparallel…
The organic system, $\kappa$-[(BEDT-TTF)$_{1-x}$(BEDT-STF)$_x$]$_2$Cu$_2$(CN)$_3$, showing the Mott transition between a nonmagnetic Mott insulating (NMI) state and a Fermi liquid (FL), is systematically studied by calorimetric…
Elemental Pr metal crystallizes in the double hexagonal close packed (dhcp) structure and is unique among rare-earth elements in featuring a localized partially filled 4f shell without ordered magnetism. Experimental evidence attributes…
We study the classical Heisenberg model for spins on a pyrochlore lattice interacting via long range dipole-dipole forces and nearest neighbor exchange. Antiferromagnetic exchange alone is known not to induce ordering in this system. We…
At low temperatures, some lattice spin models with simple ferromagnetic or antiferromagnetic interactions (for example nearest-neighbour interaction being isotropic in spin space on a bipartite three-dimensional lattice) produce…
We study theoretically the effects of f-d magnetic exchange interaction in the R$_2$Ir$_2$O$_7$ pyrochlore iridates. The R$^{3+}$ f-electrons form localized magnetic doublets due to the crystal field environment, while the Ir$^{4+}$ d-…
It is observed that interstitial hydrogen nucleii on a metallic lattice are strongly coupled to their near neighbours by the unscreened electromagnetic field mediating transitions between low-lying states. It is shown that the dominant…
This work is devoted to the analysis of orbital patterns and related to them interatomic magnetic interactions in centrosymmetric monoclinic structures of BiMnO$_3$, which have been recently determined experimentally. First, we set up an…
Microscopic investigation is performed for intersite multipolar interactions in the orbitally degenerate Anderson lattice, with CeB$_6$ taken as an exemplary target. In addition to the $f^0$ intermediate state, $f^2$ Hund's-rule ground…
An archetypical spin-glass metallic alloy, Cu0.83Mn0.17, is studied by means of an ab-initio based approach. First-principles calculations are employed to obtain effective chemical, strain-induced and magnetic exchange interactions, as well…
Among heavy fermion materials, there is a set of rare-earth intermetallics with non-Kramers Pr$^{3+}$ $4f^2$ moments which exhibit a rich phase diagram with intertwined quadrupolar orders, superconductivity, and non-Fermi liquid behavior.…
The coupling between ferroelectrics and magnetism presents a promising avenue for low-dissipation spintronic devices. However, such couplings remain rare, and the direct realization of magnetic order driven by ferroelectric switching in…
The electronic structure of lanthanide and actinide compounds is often characterized by orbital ordering of localized $f$-electrons. Density-functional theory (DFT) studies of such systems using the currently available LDA+$U$ method are…
Coexistence between ferromagnetic order and Kondo behavior has been observed in some uranium compounds. The underscreened Kondo lattice model can provide a possible description of this coexistence. Here we present a model of a lattice of…
We have performed time-resolved resonant x-ray scattering studies in the Lanthanide metal Dy to reveal the dynamic response of the helical order exchange coupling to injection of unpolarized spins. The observed spin dynamics are…
Hematite is a canted antiferromagnetic insulator, promising for applications in spintronics. Here, we present ab initio calculations of the tensorial exchange interactions of hematite and use them to understand its magnetic properties by…
Ring-exchange (RE) interaction in Mott insulator with doubly degenerate $e_g$ orbitals is studied. Hamiltonian for the RE interaction is derived by the perturbational calculation. A remarkably weak RE interaction destroys the orbital order…
We employ density functional theory within a non-collinear framework to investigate the magnetic properties of the octanuclear molecular rings Cr$_8$ and V$_8$. Our aim is to generalize the evaluation of the effective magnetic interactions…
We implement a new and accurate numerical entropic scheme to investigate the first-order transition features of the triangular Ising model with nearest-neighbor ($J_{nn}$) and next-nearest-neighbor ($J_{nnn}$) antiferromagnetic interactions…