相关论文: Inter-chain Interactions, Multi-magnon condensatio…
By exploiting density-matrix renormalization group techniques, we investigate the spin dynamics of a spin-1/2 one-dimensional J1-J2 XXZ model with competing ferromagnetic J1 and antiferromagnetic J2 exchange couplings under applied magnetic…
The spin-$1/2$ Heisenberg chain with a ferromagnetic first-neighbor exchange coupling $J_1$ and an antiferromagnetic second-neighbor $J_2$ has a Haldane dimer ground state with an extremely small spin gap. Thus, the ground state is readily…
We report on the microscopic magnetic model of a spin-1/2 magnet BaV$_3$O$_8$. In contrast to earlier phenomenological analysis, our density-functional band-structure calculations combined with quantum Monte-Carlo simulations establish a…
In a recent paper by Schmitt et al. (arXiv:1402.1091), signs of two exchange interactions of one-dimensional alternating chains in distorted honeycomb systems of Na3Cu2SbO6 and Na2Cu2TeO6 are argued by theoretical calculations. Although the…
Motivated by recent reports of a quantum disordered ground state in the triangular lattice compound NaRuO$_2$, we derive a $j_{\rm eff}=1/2$ magnetic model for this system by means of first-principles calculations. The pseudospin…
We discuss an experiment in which two magnetic insulators that both show a field-induced magnetic-ordering transition are weakly coupled to one another and are placed into an ex- ternal magnetic field. If the respective magnetic states can…
We use the density matrix renormalization group method to study the ground state `phase' diagram and some low-energy properties of isotropic antiferromagnetic spin-$1 \over 2$ and spin-$1$ chains with a next-nearest neighbor exchange $J_2…
A frustrated spin-$1/2$ XXZ chain model comprising a ferromagnetic nearest-neighbor coupling with the bond alternation, $J_1(1\pm\delta)<0$, and an antiferromagnetic second-neighbor exchange coupling $J_2>0$ is studied at zero and weak…
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…
We study the low-temperature properties of a one-dimensional spin-1/2 chain of magnetic impurities coupled to a (normal) metal environment by means of anisotropic Kondo exchange. In the case of easy-plane anisotropy, we obtain the phase…
Ground state and finite temperature properties of a system of coupled frustrated and/or dimerized spin-1/2 chains modeling e.g. the CuGeO$_3$ compound are reviewed. Special emphasis is put on the investigation of the role of impurity…
We present a comprehensive study of the magnetic properties of the long-range ordered quasi-one dimensional $J_{1}$-$J_{2}$ systems with a newly developed torque equilibrium spin-wave expansion approach, which can describe the spin Casimir…
The magnetic susceptibilities chi versus temperature T of powders and single crystals of the ambient-pressure (AP) and high-pressure (HP) phases of (VO)_{2}P_{2}O_{7} are analyzed using an accurate theoretical prediction of chi(T, J1, J2)…
We study the ground state and the magnetization process of a spin-1/2 $J_1$-$J_2$ model with a plaquette structure by using various methods. For small inter-plaquette interaction, this model is expected to have a spin-gap and we computed…
Isotropic and anisotropic magnetic behavior of the frustrated spin chain compound $\beta$-TeVO$_4$ is reported. Three magnetic transitions observed in zero magnetic field are tracked in fields applied along different crystallographic…
We investigate the phases and phase-transitions in one-dimensional alternating mixed-spin (1/2-1) chain in the presence of both frustration and anisotropy. Frustration is introduced via next-nearest-neighbor interactions, while single-ion…
Motifs of periodic modulations are encountered in a variety of natural systems, where at least two rival states are present. In strongly correlated electron systems such behaviour has typically been associated with competition between…
Magnetic excitations and the spin Hamiltonian of the spin-1 J1-J1-J2 trimer chain compound CaNi3P4O14 have been investigated by inelastic neutron scattering. Experimental data reveal gapped dispersive spin wave excitations in the 3D…
We study the spin 1/2 triangular-lattice $J_1$-$J_2$-$J_3$ antiferromagnet close to the saturation field using the dilute Bose gas theory, where the magnetic structure is determined by the condensation of magnons. We focus on the case of…
BaCo$_2$V$_2$O$_8$ is a one-dimensional antiferromagnetic spin-1/2 chain system with pronounced Ising anisotropy of the magnetic exchange. Due to finite interchain interactions long-range antiferromagnetic order develops below $T_{\rm N}…