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arXiv · 1506.00493

Spectral collapse via two-phonon interactions in trapped ions

S. Felicetti·J. S. Pedernales·I. L. Egusquiza·G. Romero·L. Lamata·D. Braak·E. Solano
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Abstract

Two-photon processes have so far been considered only as resulting from frequency-matched second-order expansions of light-matter interaction, with consequently small coupling strengths. However, a variety of novel physical phenomena arises when such coupling values become comparable with the system characteristic frequencies. Here, we propose a realistic implementation of two-photon quantum Rabi and Dicke models in trapped-ion technologies. In this case, effective two-phonon processes can be explored in all relevant parameter regimes. In particular, we show that an ion chain under bichromatic laser drivings exhibits a rich dynamics and highly counterintuitive spectral features, such as interaction-induced spectral collapse.

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S. Felicetti, J. S. Pedernales, I. L. Egusquiza, G. Romero, L. Lamata, D. Braak, E. Solano. 2015-09-15. Spectral collapse via two-phonon interactions in trapped ions. https://doi.org/10.1103/physreva.92.033817

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