Spin diffusion and the spin 1/2 XXZ chain at T = ∞ from exact diagonalization
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چکیده
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 ballistic to diffusive behavior. PACS 75.10.Jm, 75.40.Gb Typeset using REVTEX e-mail [email protected] e-mail [email protected]
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تاریخ انتشار 1997