Exchange splitting and exchange-induced non-reciprocal photonic behavior of graphene in CrI3-graphene vdW heterostructures

TL;DR

This paper investigates how exchange interactions in CrI3-graphene heterostructures influence their electromagnetic response, revealing weak effects at equilibrium but significant nonreciprocal behavior at non-equilibrium separations.

Contribution

It combines density functional theory and electromagnetic calculations to analyze exchange splitting effects in graphene within CrI3 heterostructures, highlighting conditions for strong nonreciprocal photonic behavior.

Findings

Weak nonreciprocal effects at equilibrium separation

Substantial nonreciprocal effects at non-equilibrium separations

Exchange fields reach hundreds of Tesla

Abstract

The exchange splitting and resulting electromagnetic response of graphene in a monolayer chromium triiodide(CrI3) graphene van der Waals(vdW) heterostructure are considered using a combination of density functional theory and electromagnetic calculations. Although the effective exchange fields are in the hundreds of Tesla, for the equilibrium separation non reciprocal effects are found to be weak compared to those for a comparable external magnetic bias. For non equilibrium separations, nonreciprocal effects can be substantial.