Selective transmission of Dirac electrons and ballistic magnetoresistance of \textit{n-p} junctions in graphene

TL;DR

This paper demonstrates that in graphene, an electrostatically created n-p junction selectively transmits electrons approaching perpendicularly, leading to unique magnetoresistance effects and noise characteristics.

Contribution

It reveals the angular selectivity of quasiparticle transmission in graphene n-p junctions and its implications for magnetoresistance and noise.

Findings

Selective transmission occurs only for near-perpendicular quasiparticles.

Non-local magnetoresistance effects are observed in junction arrays.

Unusual Fano factor in current noise for graphene n-p junctions.

Abstract

We show that an electrostatically created n-p junction separating the electron and hole gas regions in a graphene monolayer transmits only those quasiparticles that approach it almost perpendicularly to the n-p interface. Such a selective transmission of carriers by a single n-p junction would manifest itself in non-local magnetoresistance effect in arrays of such junctions and determines the unusual Fano factor in the current noise universal for the n-p junctions in graphene.