相关论文: Vortex-enhanced alternating order around impuritie…

We study the thermodynamics of one-dimensional quantum spin-1/2 Heisenberg ferromagnetic system with random antiferromagnetic impurity bonds. In the dilute impurity limit, we generalize the modified spin-wave theory for random spin chains,…

Higher order quantum effects on the magnetic phase diagram induced by four-spin ring exchange on plaquettes are investigated for a two-dimensional quantum antiferromagnet with S=1/2. Spatial anisotropy and frustration are allowed for. Using…

Heisenberg antiferromagnets in a strong uniform magnetic field $H$ are expected to exhibit a gapless phase with a global O(2) symmetry. In many real magnets, a small energy gap is induced by additional interactions that can be viewed as a…

In the 2-dimensional anisotropic Heisenberg model with XY-symmetry there are non-planar vortices which exhibit a localized structure of the z-components of the spins around the vortex center. We study how thermal noise induces a transition…

The ground state properties of random-exchange spin-1/2 Heisenberg antiferromagnets on the square lattice are investigated using a combination of quantum Monte Carlo simulations, exact numerical diagonalizations, and spin wave calculations.…

In the present work, we motivate and explore the dynamics of a dissipative variant of the nonlinear Schr{\"o}dinger equation under the impact of external rotation. As in the well established Hamiltonian case, the rotation gives rise to the…

Effect of randomness in the double-exchange model is studied. Large fluctuations and spatial random distribution of impurities are taken into account in an essentially exact manner by using the Monte Carlo calculation. The randomness…

We study the T=0 Kondo physics of a spin-1/2 impurity in a non-centrosymmetric metal with spin-orbit interaction. Within a simple variational approach we compute ground state properties of the system for an {\it arbitrary} form of…

At high densities fluids of strongly dipolar spherical particles exhibit spontaneous long-ranged orientational order. Typically, due to demagnetization effects induced by the long range of the dipolar interactions, the magnetization…

Using systematic effective field theory, we explore the properties of antiferromagnetic films subjected to magnetic and staggered fields that are either mutually aligned or mutually orthogonal. We provide low-temperature series for the…

Using the example of Zn-doped La2CuO4, we demonstrate that a spinless impurity doped into a non-frustrated antiferromagnet can induce substantial frustrating interactions among the spins surrounding it. This counterintuitive result is the…

In this paper we present a study of magnetic order of quantum Heisenberg spins on pyrochlore type lattices: a lattice of corner sharing tetrahedra. We use the Cluster Variation Approximation with the tetrahedron as basic cluster. We find…

Magnetoelectric properties of a coupled spin-electron model on a doubly decorated square lattice in an external electric field applied along the crystallographic axis [11] are rigorously examined with the help of generalized…

We compare the effects of in-plane non magnetic Li$^{+}$ and Zn$^{2+}$ impurities on the normal state of high-T$_{c}$ cuprates. Y NMR shows that the extra hole introduced by Li is not localized in its vicinity. The Tc depression and induced…

We investigate magnetic properties induced by a spinless impurity in strongly correlated electron systems, i.e. the Hubbard model in the spatial dimension $D=1,2,$ and 3. For the 1D system exploiting the Bethe ansatz exact solution we find…

The two-dimensional quantum Heisenberg antiferromagnet at zero temperature with two kinds of locally frustrating defects - isolated ferromagnetic bonds and impurity spins, is studied. For a quantum spin, coupled antiferromagnetically to the…

Impurity effects on the triangular antiferromagnets Ni$_{1-x}M_x$Ga$_2$S$_4$ ($M=$ Mn, Fe, Co and Zn) are studied. The 2D frozen spin-disordered state of NiGa$_2$S$_4$ is stable against the substitution of Zn$^{2+}$ ($S=0$) and Heisenberg…

We use continuum simulations to study the impact of friction on the ordering of defects in an active nematic. Even in a frictionless system, +1/2 defects tend to align side-by-side and orient antiparallel reflecting their propensity to…

It has been shown experimentally a long time ago that the magnetic ordering causes an anomalous behavior of the electron resistivity in ferromagnetic crystals. Phenomenological explanations based on the interaction between itinerant…

Physical spin configurations corresponding to topological excitations expected to be present in the XY limit of a purely quantum spin 1/2 Heisenberg ferromagnet, are probed on a two dimensional square lattice. Quantum vortices…