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Modulated phases of graphene quantum Hall polariton fluids.

ABSTRACT: There is a growing experimental interest in coupling cavity photons to the cyclotron resonance excitations of electron liquids in high-mobility semiconductor quantum wells or graphene sheets. These media offer unique platforms to carry out fundamental studies of exciton-polariton condensation and cavity quantum electrodynamics in a regime, in which electron-electron interactions are expected to play a pivotal role. Here, focusing on graphene, we present a theoretical study of the impact of electron-electron interactions on a quantum Hall polariton fluid, that is a fluid of magneto-excitons resonantly coupled to cavity photons. We show that electron-electron interactions are responsible for an instability of graphene integer quantum Hall polariton fluids towards a modulated phase. We demonstrate that this phase can be detected by measuring the collective excitation spectra, which is often at a characteristic wave vector of the order of the inverse magnetic length.

SUBMITTER: Pellegrino FM

PROVIDER: S-EPMC5114533 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Modulated phases of graphene quantum Hall polariton fluids.

Pellegrino Francesco M D FM Giovannetti Vittorio V MacDonald Allan H AH MacDonald Allan H AH Polini Marco M

Nature communications 20161114

There is a growing experimental interest in coupling cavity photons to the cyclotron resonance excitations of electron liquids in high-mobility semiconductor quantum wells or graphene sheets. These media offer unique platforms to carry out fundamental studies of exciton-polariton condensation and cavity quantum electrodynamics in a regime, in which electron-electron interactions are expected to play a pivotal role. Here, focusing on graphene, we present a theoretical study of the impact of elect ...[more]

PMID: 27841346

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