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Boundary bound states for the open Hubbard chain with boundary fields

Osamu Tsuchiya·Takashi Yamamoto
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Abstract

The boundary effects in the open Hubbard chain with boundary fields are studied. The boundary string solutions of the Bethe ansatz equations that give rise to a wave functions localized at the boundary and exponentially decreasing away from the boundary are provided. In particular, it is shown that the correct ground state of the model at half-filling contains the boundary strings.

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Osamu Tsuchiya, Takashi Yamamoto. 1997-03-10. Boundary bound states for the open Hubbard chain with boundary fields. https://doi.org/10.1143/jpsj.66.1950

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