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arXiv · 1306.4787

Route from spontaneous decay to complex multimode dynamics in cavity QED

Dmitry O. Krimer·Matthias Liertzer·Stefan Rotter·Hakan E. Tureci
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Abstract

We study the non-Markovian quantum dynamics of an emitter inside an open multimode cavity, focusing on the case where the emitter is resonant with high-frequency cavity modes. Based on a Green's function technique suited for open photonic structures, we study the crossovers between three distinct regimes as the coupling strength is gradually increased: (i) overdamped decay with a time scale given by the Purcell modified decay rate, (ii) underdamped oscillations with a time scale given by the effective vacuum Rabi frequency, and (iii) pulsed revivals. The final multimode strong coupling regime (iii) gives rise to quantum revivals of the atomic inversion on a time scale associated with the cavity round-trip time. We show that the crucial parameter to capture the crossovers between these regimes is the nonlinear Lamb shift, accounted for exactly in our formalism.

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Dmitry O. Krimer, Matthias Liertzer, Stefan Rotter, Hakan E. Tureci. 2014-03-12. Route from spontaneous decay to complex multimode dynamics in cavity QED. https://doi.org/10.1103/physreva.89.033820

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