Comment on "Magnetotransport through graphene spin valves" and its following works

TL;DR

This paper critiques previous studies on magnetotransport in graphene spin valves, demonstrating that their key formula is invalid for extended graphene systems and providing the correct formalism.

Contribution

It identifies a flaw in prior theoretical models and offers the correct formalism for analyzing magnetotransport in extended graphene systems.

Findings

Previous key formula is invalid for extended graphene.

Provides the correct formalism for extended graphene systems.

Clarifies theoretical understanding of magnetotransport in graphene.

Abstract

We show that the key formula in the works [Ding, Zhu, and Berakdar, Phys. Rev. B {\bf 79}, 045405 (2009); {\bf 84}, 115433 (2011); Ding, Zhu, Zhang, and Berakdar, Phys. Rev. B {\bf 82}, 155143 (2010)] is invalid in the extended graphene system they investigated. The correct formalism in the extended infinite system is also presented in this comment.