Quantum integrable multi-well tunneling models
  In this work we present a general construction of integrable models for boson tunneling in multi-well systems. We show how the models may be derived through the Quantum Inverse Scattering Method and solved by algebraic Bethe ansatz means. From the transfer matrix we find only two conserved operators. However, we construct additional conserved operators through a different method. As a consequence the models admit multiple pseudovacua, each associated to a set of Bethe ansatz equations. We show that all sets of Bethe ansatz equations are needed to obtain a complete set of eigenstates. 
L H Ymai, A P Tonel, A Foerster, J Links
math-ph cond-mat.quant-gas math.MP nlin.SI quant-ph