Related papers: Incommensurate phases in ferromagnetic spin-chains…
We study the one-dimensional spin-1/2 Heisenberg chain with competing ferromagnetic nearest-neighbor J_1 and antiferromagnetic next-nearest-neighbor J_2 exchange couplings in the presence of magnetic field. We use both numerical approaches…
We study the phase diagram and the commensurate-incommensurate transitions in a phase field model of a two-dimensional crystal lattice in the presence of an external pinning potential. The model allows for both elastic and plastic…
Two phase transitions in the tetragonal strongly correlated electron system CeNiAsO were probed by neutron scattering and zero field muon spin rotation. For $T <T_{N1}$ = 8.7(3) K, a second order phase transition yields an incommensurate…
The zero temperature phase diagram of the mono-axial chiral helimagnet in the magnetic field plane formed by the components parallel and perpendicular to the helical axis is thoroughly analyzed. The nature of the transition to the…
The triangular spin lattice of NiBr$_{2}$ is a canonical example of a frustrated helimagnet that shows a temperature-driven phase transition from a collinear commensurate antiferromagnetic structure to an incommensurate spin helix on…
We identify ground states of one-dimensional fermionic systems subject to competing repulsive interactions of finite range, and provide phenomenological and fundamental signatures of these phases and their transitions. Commensurable…
In the external field slightly inclined to the $x$- or y-axis of the frustrated tetragonal atiferromagnet Pr2CuO4, a transition is discovered from the phase with orthogonal antiferromagnetic spin subsystems along [1,0,0] and [0,1,0] to the…
We consider the spin-1/2 two-leg ladders with ferromagnetic (FM) interactions along legs and rungs. Using the stochastic series expansion QMC method, we study the low-temperature magnetic behavior of the system. An isolated spin-1/2 FM…
This paper examines the relation between the spin-wave instabilities of collinear magnetic phases and the resulting non-collinear phases for a geometrically-frustrated triangular-lattice antiferromagnet in the high spin limit. Using a…
Motivated by recent experiments on the frustrated quantum magnetic compound YbMgGaO4, we study an effective spin model on triangular lattice taking into account the effects of the spin-orbit coupling. We determine the classical ground-state…
In frameworks of the phenomenological approach we analyze of the phase diagram of mixed compounds. We obtain space groups of symmetry of the real structures as result of phase transition from close-packed degenerate structure. The theory of…
The effect of differently oriented magnetic field on chiral incommensurate helimagnet UPtGe is studied both experimentally and theoretically. The magnetization measurements up to the field above the saturation have revealed an isotropic…
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…
Nonreciprocity of spin wave propagation is a well-known consequence of antisymmetric exchange contributions possible in magnetic spin systems that lack inversion symmetry. In this case, it is possible for the energy of a state to depend on…
We study Heisenberg spin-1/2 and spin-1 chains with alternating ferromagnetic ($J_1^F$) and antiferromagnetic ($J_1^A$) nearest-neighbor interactions and a ferromagnetic next-nearest-neighbor interaction ($J_2^F$). In this model frustration…
The phase diagram of the spin-1/2 Heisenberg antiferromagnet on an anisotropic triangular lattice of weakly coupled chains, a model relevant to Cs2CuCl4, is investigated using a renormalization group analysis, which includes marginal…
In the quantum Hall regime of graphene, antiferromagnetic and spin-polarized ferromagnetic states at the zeroth Landau level compete, leading to a canted antiferromagnetic state depending on the direction and magnitude of an applied…
In a strongly frustrated square-lattice antiferromagnet with diagonal coupling J', for J/(2J') < 1, an incommensurate spiral state with propagation vector Q = (\pi +/- \delta, \pi +/- \delta) near (\pi,\pi) competes closely with the Neel…
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…
We study the ground-state phase diagram of an unfrustrated antiferromagnetic Ising chain with longitudinal and transverse fields in the full range of interactions: from all-to-all to nearest-neighbors. First, we solve the model analytically…