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arXiv · 1402.4838

Deformed Richardson-Gaudin model

P. Kulish·A. Stolin·H. Johannesson
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Abstract

The Richardson-Gaudin model describes strong pairing correlations of fermions confined to a finite chain. The integrability of the Hamiltonian allows for its eigenstates to be constructed algebraically. In this work we show that quantum group theory provides a possibility to deform the Hamiltonian while preserving integrability. More precisely, we use the so-called Jordanian r-matrix to deform the Hamiltonian of the Richardson-Gaudin model. In order to preserve its integrability, we need to insert a special nilpotent term into the auxiliary L-operator which generates integrals of motion of the system. Moreover, the quantum inverse scattering method enables us to construct the exact eigenstates of the deformed Hamiltonian. These states have a highly complex entanglement structure which requires further investigation.

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P. Kulish, A. Stolin, H. Johannesson. 2014-02-19. Deformed Richardson-Gaudin model. https://doi.org/10.1088/1742-6596/532/1/012012

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