title: Tamm-Hubbard surface states in the continuum.
abstract: In the framework of the Bose-Hubbard model, we show that two-particle surface bound states embedded in the continuum (BIC) can be sustained at the edge of a semi-infinite one-dimensional tight-binding lattice for any infinitesimally-small impurity potential V at the lattice boundary. Such thresholdless surface states, which can be referred to as Tamm-Hubbard BIC states, exist provided that the impurity potential V is attractive (repulsive) and the particle-particle Hubbard interaction U is repulsive (attractive), i.e. for UV < 0.
authors.affiliation: Dipartimento di Fisica, Politecnico di Milano and Istituto di Fotonica e Nanotecnologie del Consiglio Nazionale delle Ricerche, Milano, Italy. longhi@fisi.polimi.it
authors.forename: S
authors.initials: S
authors.lastname: Longhi
authors.forename: G
authors.initials: G
authors.lastname: Della Valle