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arXiv · 1805.00846

Magneto-transport controlled by Landau polariton states

Gian L. Paravicini-Bagliani·Felice Appugliese·Eli Richter·Federico Valmorra·Janine Keller·Mattias Beck·Nicola Bartolo·Clemens Rössler·Thomas Ihn·Klaus Ensslin·Cristiano Ciuti·Giacomo Scalari·Jerome Faist
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Abstract

Hybrid excitations, called polaritons, emerge in systems with strong light-matter coupling. Usually, they dominate the linear and nonlinear optical properties with applications in quantum optics. Here, we show the crucial role of the electronic component of polaritons in the magneto-transport of a cavity-embedded 2D electron gas in the ultrastrong coupling regime. We show that the linear dc resistivity is significantly modified by the coupling to the cavity even without external irradiation. Our observations confirm recent predictions of vacuum-induced modification of the resistivity. Furthermore, photo-assisted transport in presence of a weak irradiation field at sub-THz frequencies highlights the different roles of localized and delocalized states.

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Gian L. Paravicini-Bagliani, Felice Appugliese, Eli Richter, Federico Valmorra, Janine Keller, Mattias Beck, Nicola Bartolo, Clemens Rössler, Thomas Ihn, Klaus Ensslin, Cristiano Ciuti, Giacomo Scalari, Jerome Faist. 2018-10-17. Magneto-transport controlled by Landau polariton states. https://doi.org/10.1038/s41567-018-0346-y

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