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arXiv · 0808.3720

Light-matter excitations in the ultra-strong coupling regime

Aji A. Anappara·Simone De Liberato·Alessandro Tredicucci·Cristiano Ciuti·Giorgio Biasiol·Lucia Sorba·Fabio Beltram
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Abstract

In a microcavity, light-matter coupling is quantified by the vacuum Rabi frequency $Ω_R$. When $Ω_R$ is larger than radiative and non-radiative loss rates, the system eigenstates (polaritons) are linear superposition of photonic and electronic excitations, a condition actively investigated in diverse physical implementations. Recently, a quantum electrodynamic regime (ultra-strong coupling) was predicted when $Ω_R$ becomes comparable to the transition frequency. Here we report unambiguous signatures of this regime in a quantum-well intersubband microcavity. Measuring the cavity-polariton dispersion in a room-temperature linear optical experiment, we directly observe the anti-resonant light-matter coupling and the photon-energy renormalization of the vacuum field.

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Aji A. Anappara, Simone De Liberato, Alessandro Tredicucci, Cristiano Ciuti, Giorgio Biasiol, Lucia Sorba, Fabio Beltram. 2009-03-10. Light-matter excitations in the ultra-strong coupling regime. https://doi.org/10.1103/physrevb.79.201303

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