Laboratoire Kastler Brossel, Collège de France, CNRS, ENS-Université PSL, Sorbonne Université, 11, place Marcelin Berthelot, 75005 Paris, France.
Phys Rev Lett. 2019 Oct 4;123(14):143605. doi: 10.1103/PhysRevLett.123.143605.
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, which are the 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 nonclassical states in cavity and circuit quantum electrodynamics.
单模相干场中二能级系统的简单共振拉比振荡在介观尺度上揭示出复杂的特征，包括振荡的崩塌和复苏。我们使用与超导微波腔相互作用的慢速圆型里德堡原子，在前所未有的相互作用时间和光子数范围内探索了这一现象。我们展示了猫态的高效产生，这是相干分量的量子叠加，在几十到几百个光子的范围内具有几乎相反的相位和大小。我们测量了它们的魏格纳函数的切片，揭示了它们的量子相干性，并观察到了它们的快速退相干。这项实验为腔和电路量子电动力学中快速产生和操纵非经典态开辟了广阔的前景。
