Evolution of Neel order and localized spin moment in the doped two-dimensional Hubbard model

TL;DR

This paper studies how doping affects antiferromagnetic order in the 2D Hubbard model, showing that hole hopping alone does not quickly suppress Neel order, unlike in high-temperature superconductors.

Contribution

It introduces a combined semiclassical and quantum fluctuation approach to analyze Neel order suppression in doped Hubbard models, highlighting differences from experimental observations.

Findings

Hole hopping is ineffective in rapidly destroying Neel order.

Quantum disordered phase emerges after Neel order is suppressed.

Strong coupling limit yields a model of spinless fermions and bosons without gauge interactions.

Abstract

We investigate effects of doped holes' hopping on Neel order in the two-dimensional Hubbard model. Semiclassical staggered moments are computed by solving saddle point equations derived from a path-integral formalism. Effects of quantum fluctuations are taken into account by the Schwinger boson mean field theory. We argue that hopping of doped holes is ineffective in suppressing Neel order compared to rapid supprestion of Neel order in high-temperature superconductors. After destruction of Neel order, the quantum disordered phase sets in. Taking the strong coupling limit in the quantum disordered phase leads to a model of spinless fermions and bosons but no gauge field interaction.