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Transition rates via Bethe ansatz for the spin-1/2 Heisenberg chain

Daniel Biegel·Michael Karbach·Gerhard Muller
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Abstract

We use the exact determinantal representation derived by Kitanine, Maillet, and Terras for matrix elements of local spin operators between Bethe wave functions of the one-dimensional s=1/2 Heisenberg model to calculate and numerically evaluate transition rates pertaining to dynamic spin structure factors. For real solutions z_1,...,z_r of the Bethe ansatz equations, the size of the determinants is of order r x r. We present applications to the zero-temperature spin fluctuations parallel and perpendicular to an external magnetic field.

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Daniel Biegel, Michael Karbach, Gerhard Muller. 2002-05-21. Transition rates via Bethe ansatz for the spin-1/2 Heisenberg chain. https://doi.org/10.1209/epl%2Fi2002-00125-0

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