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arXiv · 0809.2552

Strong magnetic coupling of an ultracold gas to a superconducting waveguide cavity

J. Verdu·H. Zoubi·Ch. Koller·J. Majer·H. Ritsch·J. Schmiedmayer
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Abstract

Placing an ensemble of $10^6$ ultracold atoms in the near field of a superconducting coplanar waveguide resonator (CPWR) with $Q \sim 10^6$ one can achieve strong coupling between a single microwave photon in the CPWR and a collective hyperfine qubit state in the ensemble with $g_\textit{eff} / {2 π} \sim 40$ kHz larger than the cavity line width of $κ/{2 π} \sim 7$ kHz. Integrated on an atomchip such a system constitutes a hybrid quantum device, which also can be used to interconnect solid-state and atomic qubits, to study and control atomic motion via the microwave field, observe microwave super-radiance, build an integrated micro maser or even cool the resonator field via the atoms.

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J. Verdu, H. Zoubi, Ch. Koller, J. Majer, H. Ritsch, J. Schmiedmayer. 2008-09-15. Strong magnetic coupling of an ultracold gas to a superconducting waveguide cavity. https://doi.org/10.1103/physrevlett.103.043603

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