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Semiclassical description of Heisenberg models via spin-coherent states

John Schliemann·Franz G. Mertens
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Abstract

We use spin-coherent states as a time-dependent variational ansatz for a semiclassical description of a large family of Heisenberg models. In addition to common approaches we also evaluate the square variance of the Hamiltonian in terms of coherent states. This quantity turns out to have a natural interpretation with respect to time-dependent solutions of the equations of motion and allows for an estimate of quantum fluctuations in a semiclassical regime. The general results are applied to solitons, instantons and vortices in several one- and two-dimensional models.

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John Schliemann, Franz G. Mertens. 1998-10-13. Semiclassical description of Heisenberg models via spin-coherent states. https://doi.org/10.1088/0953-8984%2F10%2F5%2F016

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