Related papers: Ordered spin structures of $\beta$-MnO$_{2}$ (ruti…

The phase diagram of the Kondo lattice Hamiltonian with ferromagnetic Hund's coupling in the limit where the spin of the localized $t_{2g}$ electrons is classical is analyzed in one dimension as a function of temperature, electronic…

The ground-state magnetic phase diagram is calculated within the Hubbard and $s$-$d$ exchange (Kondo) models for square and simple cubic lattices vs. band filling and interaction parameter. The difference of the results owing to the…

We derive a spin-orbital model for insulating LaMnO_3 which fulfills the SU(2) symmetry of S=2 spins at Mn^{3+} ions. It includes the complete e_g and t_{2g} superexchange which follows from a realistic Mn^{2+} multiplet structure in cubic…

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…

We consider the ground-state phase diagram of a one-dimensional spin-1/2 XXZ chain with spatially modulated Dzyaloshinskii-Moriya interaction in the presence of applied along with the $\hat{z}$ axis alternating magnetic field. The model is…

By using variational wave functions and quantum Monte Carlo techniques, we investigate the complete phase diagram of the Heisenberg model on the anisotropic triangular lattice, where two out of three bonds have super-exchange couplings $J$…

The 3d electronic structure and phase transition in pure and Cr doped V2O3 are theoretically investigated in relation to the 3d spin-orbit interaction and lattice distortion. A model consisting of the nearest-neighbor V ion pair with full…

We use the coupled cluster method (CCM) to study the zero-temperature phase diagram of a 2D frustrated spin-half antiferromagnet, the so-called Union Jack model. It is defined on a square lattice such that all nearest-neighbor bonds are…

We study the ground state orbital ordering of $LaMnO_3$, at weak electron-phonon coupling, when the spin state is A-type antiferromagnet. We determine the orbital ordering by extending to our Jahn-Teller system a recently developed Peierls…

Magnetic phenomena of the superantiferromagnetic Ising model in both uniform longitudinal ($H$) and transverse ($\Omega $) magnetic fields are studied by employing a mean-field variational approach based on Peierls-Bogoliubov inequality for…

Previous studies have demonstrated spin-orbit torque (SOT) switching of Mn3Sn where the spin polarization lies in the kagome plane (configuration I). However, the critical current density ($ J_{crit}$) is unrealistically large ($…

We consider a lattice model of itinerant electrons coupled to an array of localized classical Heisenberg spins. The nature of the ground state ordered magnetic phases that result from the indirect spin-spin coupling mediated by the…

We present a detailed numerical study of spin and charge dynamics of the two-dimensional Kondo lattice model with hopping t and exchange J. At T=0 and J > 0, the competition between the RKKY interaction and Kondo effect triggers a quantum…

In this work, we present electronic and magnetic properties of CaMnO3 (CMO) as obtained from ab initio calculations. We identify the preferable magnetic order by means of density functional theory plus Hubbard U calculations and extract the…

The crystallographic and magnetic phase diagram of the n=2 layered manganite La2-2xSr1+2xMn2O7 in the region x=>0.5 has been studied using temperature dependent neutron powder diffraction. The magnetic phase diagram reveals a progression of…

The Heisenberg model on a triangular lattice is a prime example for a geometrically frustrated spin system. However most experimentally accessible compounds have spatially anisotropic exchange interactions. As a function of this anisotropy,…

Using modified spin wave (MSW) method, we study the $J_1-J_2$ Heisenberg model with first and second neighbor antiferromagnetic exchange interactions. For symmetric $S=1/2$ model, with the same couplings for all the equivalent neighbors, we…

We investigate the phase diagram of an anisotropic ferrimagnet spin-(1/2, 1) in the presence of a non-commuting (transverse) magnetic field. We find a magnetization plateau for the isotropic case while there is no plateau for the…

The effects of the ring-exchange Hamiltonian H_3 = J_3 sum_{<ijk>} (S_i * S_j) (S_i * S_k) on the triangular lattice are studied using classical Monte Carlo simulations. Each spin $S_i$ is treated as a classical XY spin taking on Q equally…

The magnetism of the rock-salt $fcc$ rare-earth monopnictide HoBi, a candidate topological material with extreme magnetoresistance, is investigated. From the Ho$^{3+}$ non-Kramers $J$=8 spin-orbital multiplet, the cubic crystal electric…