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arXiv · 1004.4470

Frustrated collisions and unconventional pairing on a quantum superlattice

Manuel Valiente·Matthias Kuster·Alejandro Saenz
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Abstract

We solve the problem of scattering and binding of two spin-1/2 fermions on a one-dimensional superlattice with a period of twice the lattice spacing analytically. We find the exact bound states and the scattering states, consisting of a generalized Bethe ansatz augmented with an extra scattering product due to "asymptotic" degeneracy. If a Bloch band is doubly occupied, the extra wave can be a bound state in the continuum corresponding to a single-particle interband transition. In all other cases, it corresponds to a quasi-momentum changing, frustrated collision.

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Manuel Valiente, Matthias Kuster, Alejandro Saenz. 2010-05-20. Frustrated collisions and unconventional pairing on a quantum superlattice. https://doi.org/10.1209/0295-5075%2F92%2F10001

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