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arXiv · 1207.6924

Drude weight, cyclotron resonance, and the Dicke model of graphene cavity QED

Luca Chirolli·Marco Polini·Vittorio Giovannetti·Allan H. MacDonald
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Abstract

The Dicke model of cavity quantum electrodynamics is approximately realized in condensed matter when the cyclotron transition of a two-dimensional electron gas is nearly resonant with a cavity photon mode. We point out that in the strong coupling limit the Dicke model of cavity cyclotron resonance must be supplemented by a term that is quadratic in the cavity photon field and suppresses the model's transition to a super-radiant state. We develop the theory of graphene cavity cyclotron resonance and show that the quadratic term, which is absent in graphene's low-energy Dirac model Hamiltonian, is in this case dynamically generated by virtual inter-band transitions.

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Luca Chirolli, Marco Polini, Vittorio Giovannetti, Allan H. MacDonald. 2012-07-30. Drude weight, cyclotron resonance, and the Dicke model of graphene cavity QED. https://doi.org/10.1103/physrevlett.109.267404

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