Related papers: Scaling of dynamic spin correlations in BaCu2SiGeO…
We report on band structure calculations and a microscopic model of the low-dimensional magnet beta-Cu2V2O7. Magnetic properties of this compound can be described by a spin-1/2 anisotropic honeycomb lattice model with the averaged coupling…
The two-dimensional spin-gap system ${\rm SrCu_2(BO_3)_2}$ shows unique physical properties due to the low-dimensionality character and the strong quantum fluctuations. Experimentally, 1/8-, 1/4-, and 1/3-plateaus have been observed in the…
Inelastic neutron scattering is used to identify single-particle and continuum spin excitations in the quasi-one-dimensional $S=1/2$ antiferromagnet \ba. In the data analysis, close attention is given to resolution effects. A gap in the…
Magnetic properties of the natural mineral Cu$_2$(OH)$_2$CO$_3$ (malachite) were investigated through DC and AC susceptibility measurements. The analysis of the low-temperature part reveals a quantum spin-gap behavior with $\Delta \approx…
The new antiferromagnetic (AF) compound BaCu_2Si_2O_7 is studied by magnetic susceptibility and neutron scattering techniques. The observed behavior is dominated by the presence of loosely coupled S=1/2 chains with the intrachain AF…
We present a study of the dynamic structure factor of the antiferromagnetic spin-1/2 Heisenberg chain at finite temperatures and finite magnetic fields. Using Quantum-Monte-Carlo based on the stochastic series expansion and Maximum-Entropy…
The dynamics of magnetization and energy densities are studied in the two-leg spin-1/2 ladder. Using an efficient pure-state approach based on the concept of typicality, we calculate spatio-temporal correlation functions for large systems…
Inelastic neutron scattering measurements have been performed on single crystals of the heavy fermion compound Ce$_{0.925}$La$_{0.075}$Ru$_{2}$Si$_{2}$ in broad energy [0.1, 9.5 meV] and temperature [40 mK, 294 K] ranges in order to address…
We report a neutron scattering study of the long-wavelength dynamic spin correlations in the model two-dimensional $S=1/2$ square lattice Heisenberg antiferromagnets Sr$_2$CuO$_2$Cl$_2$ and Sr$_2$Cu$_3$O$_4$Cl$_2$. The characteristic energy…
We review examples of muon-spin relaxation measurements on molecule-based magnetic coordination polymers, classified by their magnetic dimensionality. These include the one-dimensional s=1/2 spin chain Cu(pyz)(NO3)2 and the two-dimensional…
We report an investigation on structure and magnetic properties of the $S=3/2$ zigzag spin chain compound BaCoTe$_2$O$_7$. Neutron diffraction measurements reveal BaCoTe$_2$O$_7$ crystallizes in the noncentrosymmetric space group $Ama2$…
We study dynamical properties of the anisotropic triangular quantum antiferromagnet Cs_2CuCl_4. Inelastic neutron scattering measurements have established that the dynamical spin correlations cannot be understood within a linear spin wave…
A brief review of recent advances in neutron scattering studies of low-dimensional quantum magnets is followed by a particular example. The separation of single-particle and continuum states in the weakly-coupled $S=1/2$ chains system…
All eigenstates and eigenvalues are determined for the spin- 1/2 $XXZ$ chain $H = 2J \sum_i ( S_{i}^{x} S_{i + 1}^{x} + S_{i}^{y} S_{i + 1}^{y} + \Delta S_i^z S_{i + 1}^{z})$ for rings with up to N=16 spins, for anisotropies $\Delta=0 ,…
Competing magnetic interactions in low-dimensional quantum magnets can lead to the exotic ground state with fractionalized excitations. Herein, we present our results on an S = 5/2 quasi-one-dimensional spin system Bi3FeMo2O12. The…
Only 3% hole doping by Li is sufficient to suppress the long-range 3-dimensional (3D) antiferromagnetic order in La2CuO4. The spin dynamics of such a 2D spin liquid state at T << J was investigated with measurements of the dynamic magnetic…
The scaling behavior of pure gauge SU(3) in the region $\beta=5.85 - 7.60$ is examined by a Monte Carlo Renormalization Group analysis. The coupling shifts induced by factor 2 blocking are measured both on 32$^4$ and 16$^4$ lattices with…
A comprehensive theoretical and experimental study is presented of the magnetic susceptibility versus temperature \chi(T) of spin S = 1/2 two- and three-leg Heisenberg ladders and ladder oxide compounds. Extensive quantum Monte Carlo…
We study the spin fluctuation dynamics of Cu-O chains in the oxygen deficient planes of YBa(2)Cu(3)O(6+x). The chains are described by a model including antiferromagnetic interactions between the spins and Kondo-like scattering of the…
The low-dimensional s=1/2 compound (NO)[Cu(NO3)3] has recently been suggested to follow the Nersesyan-Tsvelik model of coupled spin chains. Such a system shows unbound spinon excitations and a resonating valence bond ground state due spin…