Fermionic bound states on a one-dimensional lattice

J. -P. Nguenang; S. Flach

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arXiv · 0905.1255

Fermionic bound states on a one-dimensional lattice

J. -P. Nguenang·S. Flach

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Abstract

We study bound states of two fermions with opposite spins in an extended Hubbard chain. The particles interact when located both on a site or on adjacent sites. We find three different types of bound states. Type U is predominantly formed of basis states with both fermions on the same site, while two states of type V originate from both fermions occupying neighbouring sites. Type U, and one of the states from type V, are symmetric with respect to spin flips. The remaining one from type V is antisymmetric. V-states are characterized by a diverging localization length below some critical wave number. All bound states become compact for wave numbers at the edge of the Brilloin zone.

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BibTeX RIS

J. -P. Nguenang, S. Flach. 2009-05-08. Fermionic bound states on a one-dimensional lattice. https://arxiv.org/abs/0905.1255

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