Related papers: The single-ion anisotropy in LaFeAsO
The thermodynamic properties of S>=1 ferromagnetic chains with an easy-axis single-ion anisotropy are investigated at arbitrary temperatures by both a Green-function approach, based on a decoupling of three-spin operator products, and by…
We use a Green's function method to study the temperature-dependent average moment and magnetic phase-transition temperature of the striped antiferromagnetism of LaFeAsO, and other similar compounds, as the parents of FeAs-based…
The temperature scaling of the micromagnetic Dzyaloshinsky-Moriya exchange interaction is calculated for the whole range of temperature. We use Green's function theory to derive the finite-temperature spin wave spectrum of ferromagnetic…
Exact analytical diagonalization is used to study the bipartite entanglement of the antiferromagnetic mixed spin-(1/2,$S$) Heisenberg dimer (MSHD) with the help of negativity. Under the assumption of uniaxial single-ion anisotropy affecting…
We examine the thermal properties of the spin-1 Heisenberg antiferromagnet on the honeycomb lattice in the presence of an easy-plane single-ion anisotropy as well as the effects of an additional weak in-plane easy-axis anisotropy. In…
Magnetic anisotropy plays an essential role in information technology applications of magnetic materials, providing a means to retain the long-term stability of a magnetic state in the presence of thermal fluctuations. Anisotropy consists…
The influence of uniaxial single-ion anisotropy -DSz^2 on the magnetic and thermal properties of Heisenberg antiferromagnets (AFMs) is investigated. The uniaxial anisotropy is treated exactly and the Heisenberg interactions are treated…
The effect of uniaxial single-ion anisotropy on quantum entanglement is rigorously quantified using negativity in a mixed spin-($1$,$1/2$,$1$) Heisenberg trimer, accounting for different exchange coupling constants between identical and…
The temperature dependence of mesoscopic spin-model parameters is derived in two-sublattice antiferromagnetically aligned systems based on Green's function theory. It is found that transversal spin correlations decrease the anisotropy terms…
We present an exactly solvable model of equal spin $s_1$ dimer single molecule magnets. The spins within each dimer interact via the Heisenberg and the most general quadratic global and local (single-ion) anisotropic spin interactions, and…
We present a model of equal spin $s_1$ dimer single molecule magnets. The spins within each dimer interact via the Heisenberg and the most general set of four quadratic anisotropic spin interactions with respective strengths $J$ and…
The concept of negativity is adapted in order to explore the quantum and thermal entanglement of the mixed spin-(1/2,$S$) Heisenberg dimers in presence of an external magnetic field. The mutual interplay between the spin size $S$, XXZ…
We present a spin-rotation-invariant Green-function theory for the dynamic spin susceptibility in the spin-1/2 antiferromagnetic Heisenberg model on a stacked honeycomb lattice. Employing a generalized mean-field approximation for arbitrary…
we investigate the thermodynamic properties of weakly anisotropic disordered magnetic chains where the nearest-neighbor Heisenberg exchange coupling is the dominant spin-spin interaction. In addition to the exchange interaction, there is…
In this study, we have investigated ground state properties of one-dimensional antiferromagnetic spin-1 chain with single-ion anisotropy at very low temperatures using the Transfer Matrix method. Magnetic plateaus, phase diagram, specific…
We study the zero-temperature phase diagram of the $J_{1}^{XXZ}$--$J_{2}^{XXZ}$ Heisenberg model for spin-1 particles on an infinite square lattice interacting via nearest-neighbour ($J_1 \equiv 1$) and next-nearest-neighbour ($J_2 > 0$)…
We study the thermodynamics of the spin-$S$ two-dimensional quantum Heisenberg antiferromagnet on the square lattice with nearest ($J_1$) and next-nearest ($J_2$) neighbor couplings in its collinear phase ($J_2/J_1>0.5$), using the…
Using the spherically symmetric self-consistent Green's function method, we consider thermodynamic properties of the $S=1/2$ $J_1$-$J_2$ Heisenberg model on the 2D square lattice. We calculate the temperature dependence of the spin-spin…
The anisotropic XXZ spin-1/2 Heisenberg chain is studied using renormalization-group theory. The specific heats and nearest-neighbor spin-spin correlations are calculated thoughout the entire temperature and anisotropy ranges in both…
The field-driven reorientation transition of an anisotropic ferromagnetic monolayer is studied within the context of a finite-temperature Green's function theory. The equilibrium state and the field dependence of the magnon energy gap $E_0$…