Related papers: Impurity spin relaxation in S=1/2 XX chains
A model consisting in two quantum XX spin chains, one homogeneous and the second with random couplings drawn from a binary distribution, is considered. The two chains are coupled to two different non-local thermal baths and their dynamics…
The correlations, entanglement entropy, and fidelity susceptibility are calculated for a one-dimensional spin-1/2 XXZ chain with anisotropic power-law long range interactions by employing the density matrix renormalization group method. In…
An interesting feature of spin-1/2 chains with a gap is that they undergo a commensurate-incommensurate transition in the presence of an external magnetic field $H$. The system is in a gapless incommensurate regime for all values of the…
In this first paper, we start the analysis of correlation functions of quantum spin chains with general integrable boundary conditions. We initiate these computations for the open XXX spin 1/2 quantum chains with some unparallel magnetic…
We study the local thermal entanglement in a spin-1/2 Ising-$XXZ$ diamond structure with two impurities. In this spin chain, we have the two impurities with an isolated $XXZ$ dimer between them. We focus on the study of the thermal…
We study effects of nonmagnetic impurities in a spin-1/2 frustrated triangular antiferromagnet with the aim of understanding the observed broadening of $^{13}$C NMR lines in the organic spin liquid material $\kappa$-(ET)$_2$Cu$_2$(CN)$_3$.…
We study the low-temperature properties of the generalized Anderson impurity model in which two localized configurations, one with two doublets and the other with a triplet, are mixed by two degenerate conduction channels. By using the…
We introduce and study a simplification of the symmetric single-impurity Kondo model. In the Ising-Kondo model, host electrons scatter off a single magnetic impurity at the origin whose spin orientation is dynamically conserved. This…
We show how to compute analytically time and space dependent correlations in one dimensional quantum integrable systems with an impurity. Our approach is based on a description of these systems in terms of massless scattering of…
We consider a single impurity with spin $S$ embedded in a three-dimensional antiferromagnetic system which is close to the quantum critical point (QCP), separating magnetically ordered and disordered phases. Approaching the QCP from the…
Spin density matrices of the system, containing arbitrary even number N of indistinguishable fermions with spin S = 1/2, described by antisymmetric wave function, have been calculated. The indistinguishability and the Pauli principles are…
We study Kondo physics in the algebraic spin liquid, recently proposed to describe $ZnCu_{3}(OH)_{6}Cl_{2}$ [Phys. Rev. Lett. {\bf 98}, 117205 (2007)]. Although spin dynamics of the algebraic spin liquid is described by massless Dirac…
We study the disordered Heisenberg spin chain, which exhibits many body localization at strong disorder, in the weak to moderate disorder regime. A continued fraction calculation of dynamical correlations is devised, using a variational…
The bulk properties and impurity effect in the one-dimensional S=1/2 Heisenberg model with dimerization and next-nearest-neighbor exchange are studied by the density matrix renormalization group (DMRG) and exact diagonalization methods.…
We present accurate numerical estimates for the correlation amplitudes of leading and main subleading terms of the two- and four-spin correlation functions in the one-dimensional spin-1/2 XXZ model under a magnetic field. These data are…
The Jordan--Wigner transformation plays an important role in spin models. However, the non-locality of the transformation implies that a periodic chain of $N$ spins is not mapped to a periodic or an anti-periodic chain of lattice fermions.…
SU(3)-invariant "spin" chains with a single impurity, such as a modified exchange coupling on one link, are analyzed using boundary conformal field theory techniques. These chains are equivalent to a special case of the "tJV" model, i.e.…
The $s=1$ Heisenberg Antiferromagnet is studied in the presence of two kinds of local impurities. First, a perturbed antiferromagnetic bond with $J'\ne J$ at the center of an even-length open chain is considered. Using the density matrix…
We study high-temperature spin transport through an anisotropic spin-1/2 Heisenberg chain in which integrability is broken by a single impurity close to the center of the chain. For a finite impurity strength, the level spacing statistics…
The $S=1/2$ XXZ spin chain with the staggered XY anisotropy $$ H = J \sum_{n}^{N} (S^{x}_{n} S^{x}_{n+1} + S^{y}_{n} S^{y}_{n+1} + \Delta S^{z}_{n} S^{z}_{n+1}) - \delta \sum_{n}^{N} (-1)^{n} (S^{x}_{n} S^{x}_{n+1} - S^{y}_{n} S^{y}_{n+1})…