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arXiv quant-ph/04071702004-07-21quant-ph

Quantum spin tunneling in a soluble quasi-spin model: An angle-based potential description

D. Galetti, C. L. Lima, B. M. Pimentel

备注：: 6 figures .eps

英文摘要：

We propose an approach which allows to construct and use a potential function written in terms of an angle variable to describe interacting spin systems. We show how this can be implemented in the Lipkin-Meshkov-Glick, here considered a paradigmatic spin model. It is shown how some features of the energy gap can be interpreted in terms of a spin tunneling. A discrete Wigner function is constructed for a symmetric combination of two states of the model and its time evolution is obtained. The physical information extracted from that function reinforces our description of phase oscillations in a potential.

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