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arXiv · 1505.02858

Correlated emission lasing in harmonic oscillators coupled via a single three-level artificial atom

Z. H. Peng·Yu-xi Liu·J. T. Peltonen·T. Yamamoto·J. S. Tsai·O. Astafiev
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Abstract

A single superconducting artificial atom provides a unique basis for coupling electromagnetic fields and photons hardly achieved with a natural atom. Bringing a pair of harmonic oscillators into resonance with transitions of the three-level atom converts atomic spontaneous processes into correlated emission dynamics. We demonstrate two-mode correlated emission lasing on harmonic oscillators coupled via the fully controllable three-level artificial atom. Correlation of two different color emissions reveals itself as equally narrowed linewiths and quench of their mutual phase-diffusion. The mutual linewidth is more than four orders of magnitude narrower than the Schawlow-Townes limit. The interference between the different color lasing fields demonstrates the two-mode fields are strongly correlated.

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Z. H. Peng, Yu-xi Liu, J. T. Peltonen, T. Yamamoto, J. S. Tsai, O. Astafiev. 2015-05-12. Correlated emission lasing in harmonic oscillators coupled via a single three-level artificial atom. https://doi.org/10.1103/physrevlett.115.223603

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