Quantum Rabi oscillations in coherent and in mesoscopic "cat" field states

F. Assemat , D. Grosso , A. Signoles , A. Facon , I. Dotsenko (1) , S. Haroche (2, 3) , J. m. M Raimond , Michel Brune (3) , S. Gleyzes (4)

1 LKB (Jussieu) - Laboratoire Kastler Brossel
2 LSH-ENS - Laboratoire de Spectroscopie Hertzienne de l'ENS
3 LKB [Collège de France] - Laboratoire Kastler Brossel
4 LKB (Lhomond) - Laboratoire Kastler Brossel

The simple resonant Rabi oscillation of a two-level system in a single-mode coherent field reveals complex features at the mesoscopic scale, with oscillation collapses and revivals. Using slow circular Rydberg atoms interacting with a superconducting microwave cavity, we explore this phenomenon in an unprecedented range of interaction times and photon numbers. We demonstrate the efficient production of 'cat' states, quantum superposition of coherent components with nearly opposite phases and sizes in the range of few tens of photons. We measure cuts of their Wigner functions revealing their quantum coherence and observe their fast decoherence. This experiment opens promising perspectives for the rapid generation and manipulation of non-classical states in cavity and circuit Quantum Electrodynamics.

Domaines: Physique Quantique [quant-ph]

F. Assemat, D. Grosso, A. Signoles, A. Facon, I. Dotsenko, et al.. Quantum Rabi oscillations in coherent and in mesoscopic "cat" field states. Physical Review Letters, 2019, 123 (14), ⟨10.1103/PhysRevLett.123.143605⟩. ⟨hal-02323657⟩