Spin diffusion and the spin-1/2XXZchain atT=∞from exact diagonalization

Spin diffusion and the spin 1/2 XXZ chain at T = ∞ from exact diagonalization

We study the long time behavior of the zz and xx time dependent autocorrelation function of the spin 1/2 XXZ chain at T = ∞ by exact diagonalizations on a chain of 16 sites. We find that the numerical results for the zz correlation are very well fit by the formula t−d[A+Be−γ(t−t0) cos Ω(t− t0)]. From this we estimate d as a function of the anisotropy of the chain and study the crossover from ba...

Exact diagonalization studies of doped Heisenberg spin rings

Motivated bymagnetization studies of the “telephon number compound” Sr14Cu24O41 we investigate doped Heisenberg spin rings by means of complete numerical diagonalization of a Heisenberg Hamiltonian that depends parametrically on hole positions. A comparison with experimental magnetization data reveals rather accurate information about the screened electrostatic interaction between the charged h...

Spin dynamics in a double quantum dot: Exact diagonalization study

High Temperature Expansion and Exact Diagonalization of the Rhodium Nuclear Spin System Compared to Experimental Results

Quantum Critical Behavior of the Infinite-range Transverse Ising Spin Glass : An Exact Numerical Diagonalization Study

We report exact numerical diagonalization results of the infinite-range Ising spin glass in a transverse field Γ at zero temperature. Eigenvalues and eigenvectors are determined for various strengths of Γ and for system sizes N ≤ 16. We obtain the moments of the distribution of the spin-glass order parameter, the spin-glass susceptibility and the mass gap at different values of Γ. The disorder ...