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arXiv · 1611.09151

THz ultrastrong light-matter coupling

Giacomo Scalari·Curdin Maissen·Sara Cibella·Roberto Leoni·Christian Reichl·Werner Wegscheider·Mattias Beck·Jérôme Faist
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Abstract

Cavity photon resonators with ultrastrong light-matter interactions are attracting interest both in semiconductor and superconducting systems displaying the capability to manipulate the cavity quantum electrodynamic ground state with controllable physical properties. Here we review a series of experiments aimed at probing the ultrastrong light-matter coupling regime, where the vacuum Rabi splitting $\Omega$ is comparable to the bare transition frequency $\omega$ . We present a new platform where the inter-Landau level transition of a two-dimensional electron gas (2DEG) is strongly coupled to the fundamental mode of deeply subwavelength split-ring resonators operating in the mm-wave range. Record-high values of the normalized light-matter coupling ratio $\frac{\Omega}{\omega}= 0.89$ are reached and the system appears highly scalable far into the microwave range.

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Giacomo Scalari, Curdin Maissen, Sara Cibella, Roberto Leoni, Christian Reichl, Werner Wegscheider, Mattias Beck, Jérôme Faist. 2016-11-28. THz ultrastrong light-matter coupling. https://arxiv.org/abs/1611.09151

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