1205.6431 (Jiang-min Zhang et al.)

Two-Particle Bound States in the Continuum realized in the
one-dimensional Hubbard Model with an Impurity    [PDF]

Jiang-min Zhang, Daniel Braak, Marcus Kollar

We report a bound state, which is embedded in the continuum spectrum, of the one-dimensional two-particle (Bose or Fermion) Hubbard model with an impurity potential. The state has the Bethe-ansatz form, although this model is nonintegrable. Moreover, for a wide region in parameter space, its energy is located in the continuum band. A remarkable advantage of this state with respect to similar states in other systems is the simple analytical form of the wave function and eigenvalue. This state can be tuned in and out of the continuum continuously.

View original: http://arxiv.org/abs/1205.6431