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arXiv · 1604.03663

Quantum coherence between cavity and artificial atom in a superconducting circuit QED ladder system

Qichun Liu·Han Cai·Yingshan Zhang·Jianshe Liu·Wei Chen
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Abstract

We have created a quantum three-level ladder system with the cavity dispersive energy level in a superconducting circuit quantum electrodynamics system consisting of a transmon qubit and a cavity, and have directly observed the Autler-Townes splitting effect instead of representing it by the probability of the qubit being at each level. A coupler tone is applied on the transition between the second excited state of transmon and cavity dispersive level, while the cavity spectrum is probed. A doublet transmission and anormalous dispersion spectrum of the cavity level is clearly shown. The inverse Fourier transform of cavity spectrum indicates that there is a quantum coherence Rabi oscillation of the populations between cavity and qubit.

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Qichun Liu, Han Cai, Yingshan Zhang, Jianshe Liu, Wei Chen. 2016-04-13. Quantum coherence between cavity and artificial atom in a superconducting circuit QED ladder system. https://arxiv.org/abs/1604.03663

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