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Coordinate Representation of the Two-Spinon wavefunction and Spinon Interaction

B. A. Bernevig·D. Giuliano·R. B. Laughlin
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Abstract

By deriving and studying the coordinate representation for the two-spinon wavefunction, we show that spinon excitations in the Haldane-Shastry model interact. The interaction is given by a short-range attraction and causes a resonant enhancement in the two-spinon wavefunction at short separations between the spinons. We express the spin susceptibility for a finite lattice in terms of the resonant enhancement, given by the two-spinon wavefunction at zero separation. In the thermodynamic limit, the spinon attraction turns into the square-root divergence in the dynamical spin susceptibility.

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B. A. Bernevig, D. Giuliano, R. B. Laughlin. 2000-11-16. Coordinate Representation of the Two-Spinon wavefunction and Spinon Interaction. https://doi.org/10.1103/physrevb.64.024425

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