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arXiv · 1108.4507

Quasi-Exactly Solvable Models Derived from the Quasi-Gaudin Algebra

Yuan-Harng Lee·Jon Links·Yao-Zhong Zhang
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Abstract

The quasi-Gaudin algebra was introduced to construct integrable systems which are only quasi-exactly solvable. Using a suitable representation of the quasi-Gaudin algebra, we obtain a class of bosonic models which exhibit this curious property. These models have the notable feature that they do not preserve U(1) symmetry, which is typically associated to a non-conservation of particle number. An exact solution for the eigenvalues within the quasi-exactly solvable sector is obtained via the algebraic Bethe ansatz formalism.

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Yuan-Harng Lee, Jon Links, Yao-Zhong Zhang. 2011-08-23. Quasi-Exactly Solvable Models Derived from the Quasi-Gaudin Algebra. https://doi.org/10.1088/1751-8113/44/48/482001

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