We perform quantum non-demolition (QND) photon counting on a microwave field trapped in a very high Q superconducting cavity, employing circular Rydberg atoms as non-absorbing light probes. Beyond realizing fundamental tests of quantum measurement theory, we use this QND method to prepare non-classical Fock and Schrodinger cat states of the field and to reconstruct their Wigner functions. Monitoring the evolution of these functions provides a direct observation of the decoherence process. Quantum feedback procedures will enable us to steer the field towards target states and to protect them against decoherence.
|Number of pages||7|
|Publication status||Published - 1 Dec 2009|
- quantum mechanics
- molecular physics
- microwave fileds
- quantum optics
Haroche, S., Dotsenko, I., Deleglise, S., Sayrin, C., Zhou, X., Gleyzes, S., ... Raimond, J-M. (2009). Manipulating and probing microwave fields in a cavity by quantum non-demolition photon counting. Physica Scripta, 2009(T137), . https://doi.org/10.1088/0031-8949/2009/T137/014014