Phase transitions in the one-dimensional ionic Hubbard model

TL;DR

This paper investigates quantum phase transitions in the one-dimensional ionic Hubbard model using matrix product operator methods, revealing clear signatures of Mott transitions through various physical observables.

Contribution

It demonstrates the effectiveness of the matrix product operator approach in studying itinerant fermion systems and characterizes phase transitions in the ionic Hubbard model.

Findings

Identification of Mott transition signatures in density and entanglement entropy

Validation of matrix product operator method for fermionic systems

Ground state characterization across different potentials

Abstract

We study quantum phase transitions by measuring the bond energy, the number density, and the half-chain entanglement entropy in the one-dimensional ionic Hubbard model. By performing the infinite density matrix renormalization group with matrix product operator, we obtain ground states as the canonical form of matrix product states. Depending on the chemical potential and the staggered potential, the number density and the half-chain entanglement entropy shows clear signatures of the Mott transition. Our results confirm the success of the matrix product operator method for investigation of itinerant fermion systems.