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arXiv · 1112.1740

A variational approach for the Quantum Inverse Scattering Method

A. Birrell·P. S. Isaac·J. Links
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Abstract

We introduce a variational approach for the Quantum Inverse Scattering Method to exactly solve a class of Hamiltonians via Bethe ansatz methods. We undertake this in a manner which does not rely on any prior knowledge of integrability through the existence of a set of conserved operators. The procedure is conducted in the framework of Hamiltonians describing the crossover between the low-temperature phenomena of superconductivity, in the Bardeen-Cooper-Schrieffer (BCS) theory, and Bose-Einstein condensation (BEC). The Hamiltonians considered describe systems with interacting Cooper pairs and a bosonic degree of freedom. We obtain general exact solvability requirements which include seven subcases which have previously appeared in the literature.

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A. Birrell, P. S. Isaac, J. Links. 2011-12-08. A variational approach for the Quantum Inverse Scattering Method. https://doi.org/10.1088/0266-5611%2F28%2F3%2F035008

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