New possibility of the ground state of quarter-filled one-dimensional strongly correlated electronic system interacting with localized spins

TL;DR

This study numerically investigates a quarter-filled one-dimensional strongly correlated electronic system with localized spins, revealing charge order stabilization, ferromagnetism emergence, and potential for magnetic control of charge states relevant to giant magnetoresistance.

Contribution

It demonstrates how coupling with localized spins stabilizes charge order and induces ferromagnetism, providing new insights into magnetic control of electronic states in correlated systems.

Findings

Charge order is stabilized by small coupling with localized spins.

Large coupling leads to independent spin and charge behavior with ferromagnetism.

Charge order can be controlled by magnetic fields, suggesting giant negative magnetoresistance.

Abstract

We study numerically the ground state properties of the one-dimensional quarter-filled strongly correlated electronic system interacting antiferromagnetically with localized $S=1/2$ spins. It is shown that the charge-ordered state is significantly stabilized by the introduction of relatively small coupling with the localized spins. When the coupling becomes large the spin and charge degrees of freedom behave quite independently and the ferromagnetism is realized. Moreover, the coexistence of ferromagnetism with charge order is seen under strong electronic interaction. Our results suggest that such charge order can be easily controlled by the magnetic field, which possibly give rise to the giant negative magnetoresistance, and its relation to phthalocyanine compounds is discussed.