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arXiv · hep-th/9510131

Exact Bethe ansatz solution of nonultralocal quantum mKdV model

Anjan Kundu
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Abstract

A lattice regularized Lax operator for the nonultralocal modified Korteweg de Vries (mKdV) equation is proposed at the quantum level with the basic operators satisfying a $q$-deformed braided algebra. Finding further the associated quantum $R$ and $Z$-matrices the exact integrability of the model is proved through the braided quantum Yang--Baxter equation, a suitably generalized equation for the nonultralocal models. Using the algebraic Bethe ansatz the eigenvalue problem of the quantum mKdV model is exactly solved and its connection with the spin-$\ha$ XXZ chain is established, facilitating the investigation of the corresponding conformal properties.

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Anjan Kundu. 1995-10-18. Exact Bethe ansatz solution of nonultralocal quantum mKdV model. https://doi.org/10.1142/s0217732395003094

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