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arXiv quant-ph/99080441999-08-13quant-ph

Semiclassical density of degeneracies in quantum regular systems

A. J. Fendrik, M. J. Sánchez

备注：: 25 pages, 7 figures . Submitted to PRE
DOI：: 10.1088/0305-4470/33/12/303

英文摘要：

The spectrum of eigenenergies of a quantum integrable system whose hamiltonian depends on a single parameter shows degeneracies (crossings) when the parameter varies. We derive a semiclassical expression for the density of crossings in the plane energy-parameter, that is the number of crossings per unit of energy and unit of parameter, in terms of classical periodic orbits. We compare the results of the semiclassical formula with exact quantum calculations for two specific quantum integrable billiards.

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