Exciton swapping in a twisted graphene bilayer as a solid-state realization of a two-brane model

TL;DR

This paper proposes a novel exciton swapping mechanism in twisted graphene bilayers, modeled as a two-brane system, with potential applications in tunable optical filtering and insights into braneworld theories.

Contribution

It introduces a formalism describing turbostratic graphene layers as a noncommutative two-sheeted spacetime, linking condensed matter physics with high energy braneworld models.

Findings

Exciton swapping can occur under specific conditions in twisted graphene bilayers.

A magnetically tunable optical filter based on this effect is proposed.

The model connects interlayer coupling to braneworld concepts.

Abstract

It is shown that exciton swapping between two graphene sheets may occur under specific conditions. A magnetically tunable optical filter is described to demonstrate this new effect. Mathematically, it is shown that two turbostratic graphene layers can be described as a "noncommutative" two-sheeted (2+1)-spacetime thanks to a formalism previously introduced for the study of braneworlds in high energy physics. The Hamiltonian of the model contains a coupling term connecting the two layers which is similar to the coupling existing between two braneworlds at a quantum level. In the present case, this term is related to a K-K' intervalley coupling. In addition, the experimental observation of this effect could be a way to assess the relevance of some theoretical concepts of the braneworld hypothesis.