Related papers: Thouless number and spin diffusion in quantum Heis…
We present the results of muon-spin relaxation measurements of spin excitations in the one-dimensional quantum Heisenberg antiferromagnet Cu(pyz)(NO$_{3}$)$_{2}$. Using density-functional theory we propose muon sites and assess the degree…
We study Dyson's classical $r$-component ferromagnetic hierarchical model with a long range interaction potential $U(i,j)= -l(d(i,j)) d^{-2}(i,j)$, where $d(i,j)$ denotes the hierarchical distance. We prove a conjecture of Dyson, which…
Using the Bethe ansatz method, the zero frequency contribution (Drude weight) to the spin current correlations is analyzed for the easy plane antiferromagnetic Heisenberg model. The Drude weight is a monotonically decreasing function of…
We describe quantum limits to field sensing that relate noise, geometry and measurement duration to fundamental constants, with no reference to particle number. We cast the Tesche and Clarke (TC) bound on dc-SQUID sensitivity as such a…
We study the dynamics of spin currents in the XX spin-1/2 ladder at finite temperature. Within the framework of linear response theory, we numerically calculate autocorrelation functions for quantum systems larger than what is accessible…
A consideration of waves propagating parallel to the external magnetic field is presented. The dielectric permeability tensor is derived from quantum kinetic equations with non-trivial equilibrium spin-distribution functions (NTESDF) in the…
We address the nature of spin transport in the integrable XXZ spin chain, focusing on the isotropic Heisenberg limit. We calculate the diffusion constant using a kinetic picture based on generalized hydrodynamics combined with Gaussian…
We present numerical results for finite-temperature $T>0$ thermodynamic quantities, entropy $s(T)$, uniform susceptibility $\chi_0(T)$ and the Wilson ratio $R(T)$, for several isotropic $S=1/2$ extended Heisenberg models which are prototype…
We perform a theoretical investigation on the time evolution of spin pulses in an $n$-type GaAs (001) quantum well with and without external electric field at high temperatures by constructing and numerically solving the kinetic spin Bloch…
We use numerical techniques to study dynamical properties at finite temperature ($T$) of the Heisenberg spin chain with random exchange couplings, which realizes the random singlet (RS) fixed point in the low-energy limit. Specifically, we…
We present a mechanism for displaying the transmission property of the discrete Heisenberg ferromagnetic spin chain (DHF) via a geometric approach. By the aid of a discrete nonlinear Schr\"odinger-like equation which is the discrete gauge…
We investigate spin quantum-fluctuation effects that originate from the Heisenberg uncertainty principle during the dynamical cycle of disentanglement, entanglement, and re-disentanglement between itinerant electrons and localized magnetic…
We study experimentally the far-from-equilibrium dynamics in ferromagnetic Heisenberg quantum magnets realized with ultracold atoms in an optical lattice. After controlled imprinting of a spin spiral pattern with adjustable wave vector, we…
The dynamics of spin at finite temperature in the spin-1/2 Heisenberg chain was found to be superdiffusive in numerous recent numerical and experimental studies. Theoretical approaches to this problem have emphasized the role of nonabelian…
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…
Using the Landau Fermi liquid theory we have discovered a new regime for the propagation of spin waves in a quasi-equilibrium spin systems. We have determined the dispersion relation for the transverse spin waves and found that one of the…
We present a numerical study on the spin and thermal conductivities of the spin-1 Heisenberg chain in the high temperature limit, in particular of the Drude weight contribution and frequency dependence. We use the Exact Diagonalization and…
The spin diffusion/transport in $n$-type (001) GaAs quantum well at high temperatures ($\ge120$ K) is studied by setting up and numerically solving the kinetic spin Bloch equations together with the Poisson equation self-consistently. All…
We show that the probability distribution corresponding to a fully random tracial state of a system of spin-S particles satisfies a diffusion-like equation. The diffusion coefficient turns out to be equal to $S(S+1)/6$, where $S$ is the…
A perturbation spin-wave theory for the quantum Heisenberg antiferromagnets on a square lattice is proposed to calculate the uniform static magnetic susceptibility at finite temperatures, where a divergence in the previous theories due to…