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Exact four-spinon dynamical correlation function in isotropic Heisenberg model

A. Abada·A. H. Bougourzi·S. Seba·B. Si-Lakhal
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Abstract

We discuss some properties of the exact four-spinon dynamical correlation function $S_4$ in the antiferromagnetic spin 1/2 $XXX$-model, the expression of which we derived recently. We show that the region in which it is not identically zero is different from and larger than the spin-wave continuum. We describe its behavior as a function of the neutron momentum transfer $k$ for fixed values of the neutron energy $ω$ and compare it to the one corresponding to the exact two-spinon dynamical correlation function $S_2$. We show that the overall shapes are quite similar, even though the expression of $S_4$ is much more involved than that of $S_2$. We finish with concluding remarks.

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A. Abada, A. H. Bougourzi, S. Seba, B. Si-Lakhal. 1998-05-15. Exact four-spinon dynamical correlation function in isotropic Heisenberg model. https://arxiv.org/abs/cond-mat/9802271

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