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arXiv · 1708.07773

Landau polaritons in highly non-parabolic 2D gases in the ultra-strong coupling regime

Janine Keller·Giacomo Scalari·Felice Appugliese·Shima Rajabali·Mattias Beck·Johannes Haase·Christian A. Lehner·Werner Wegscheider·Michele Failla·Maksym Myronov·David R. Leadley·James Lloyd-Hughes·Pierre Nataf·Jerome Faist
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Abstract

We probe ultra-strong light matter coupling between metallic terahertz metasurfaces and Landau-level transitions in high mobility 2D electron and hole gases. We utilize heavy-hole cyclotron resonances in strained Ge and electron cyclotron resonances in InSb quantum wells, both within highly non-parabolic bands, and compare our results to well known parabolic AlGaAs/GaAs quantum well (QW) systems. Tuning the coupling strength of the system by two methods, lithographically and by optical pumping, we observe a novel behavior clearly deviating from the standard Hopfield model previously verified in cavity quantum electrodynamics: an opening of a lower polaritonic gap.

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Janine Keller, Giacomo Scalari, Felice Appugliese, Shima Rajabali, Mattias Beck, Johannes Haase, Christian A. Lehner, Werner Wegscheider, Michele Failla, Maksym Myronov, David R. Leadley, James Lloyd-Hughes, Pierre Nataf, Jerome Faist. 2019-12-30. Landau polaritons in highly non-parabolic 2D gases in the ultra-strong coupling regime. https://doi.org/10.1103/physrevb.101.075301

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