The use of Entanglement Entropy to Classify Quantum Phase Transitions in 1D Ultracold Spinor Bosons.

Abstract

In this paper, we discuss a novel method based on a quantum-information-tool suitable to identify and characterize quantum-phases and phase transitions in a broad set of lattice models relevant in condensed-matter systems. The method relies on the entanglement entropy which, for instance, can be calculated using the Matrix Product State (MPS) algorithm, or any other method, for several system sizes to perform an appropriate scaling. Particularly, this advanced method has been applied for a finite 1D system of repulsively interacting spin-1 bosons and obtaining the universality class via the calculation of the central charge for the external field-induced phase transition between the dimerized phase and the XY-nematic phase in the antiferromagnetic regime. Finally, we briefly discuss how this method has been recently used to identify topological phases.