Two-fluid coexistence in a spinless fermions chain with pair hopping

Abstract : We show that a simple one-dimensional model of spinless fermions with pair hopping displays a phase in which a Luttinger liquid of paired fermions coexists with a Luttinger liquid of unpaired fermions. Our results are based on extensive numerical density-matrix renormalization-group calculations and are supported by a two-fluid model that captures the essence of the coexistence region.

Lorenzo Gotta 1 Leonardo Mazza 1 Pascal Simon 2 Guillaume Roux 1
1 LPTMS – Laboratoire de Physique Théorique et Modèles Statistiques
2 LPS – Laboratoire de Physique des Solides