V. E. Korepin, S. Lukyanov, Y. Nishiyama, M. Shiroishi
Asymptotic Behavior of the Emptiness Formation Probability
in the Critical Phase of XXZ Spin Chain
(197K, Postscript)
ABSTRACT. We study the
Emptiness Formation Probability
(EFP) for the spin 1/2 $XXZ$ spin chain.
EFP $P(n)$ detects a formation of ferromagnetic string of the
length $n$ in the ground state.
It is expected that EFP decays in a Gaussian way for large strings
Here, we propose the explicit expressions for
the rate of Gaussian decay ${C}$ as well as for the exponent $\gamma$.In order to confirm the validity of our formulae,
we employed an {\it ab initio} simulation technique of the
density-matrix renormalization group to simulate
$XXZ$ spin chain of sufficient length.
Furthermore, we performed Monte-Carlo integration of
the Jimbo-Miwa multiple integral for ${P(n)}$.
Those numerical results for ${P(n)}$ support our formulae
fairly definitely.