Giant Magnetoresistance in Hubbard Chains

TL;DR

This paper demonstrates that the one-dimensional Hubbard model with periodic on-site interactions can exhibit giant magnetoresistance, showing significant charge transport enhancement under an external magnetic field through unbiased numerical methods.

Contribution

It reveals that minimal ingredients in a Hubbard chain suffice to produce giant magnetoresistance without separate itinerant or localized charge entities.

Findings

Magnetoresistance observed in the Hubbard chain with periodic interactions.

Charge transport is dramatically enhanced by an external magnetic field.

The phenomenon is explained without distinguishing itinerant and localized charges.

Abstract

We use numerically unbiased methods to show that the one-dimensional Hubbard model with periodically distributed on-site interactions already contains the minimal ingredients to display the phenomenon of magnetoresistance; i.e., by applying an external magnetic field, a dramatic enhancement on the charge transport is achieved. We reach this conclusion based on the computation of the Drude weight and of the single-particle density of states, applying twisted boundary condition averaging to reduce finite-size effects. The known picture that describes the giant magnetoresistance, by interpreting the scattering amplitudes of parallel or antiparallel polarized currents with local magnetizations, is obtained without having to resort to different entities; itinerant and localized charges are indistinguishable.