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arXiv · 1705.11118

Vacuum-induced Autler-Townes splitting in a superconducting artificial atom

Z. H. Peng·J. H. Ding·Y. Zhou·L. L. Ying·Z. Wang·L. Zhou·L. M. Kuang·Yu-xi Liu·O. Astafiev·J. S. Tsai
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Abstract

We experimentally study a vacuum-induced Autler-Townes doublet in a superconducting three-level artificial atom strongly coupled to a coplanar waveguide resonator and simultaneously to a transmission line. The Autler-Townes splitting is observed in the reflection spectrum from the three-level atom in a transition between the ground state and the second excited state when the transition between the two excited states is resonant with a resonator. By applying a driving field to the resonator, we observe a change in the regime of the Autler-Townes splitting from quantum (vacuum-induced) to classical (with many resonator photons). Furthermore, we show that the reflection of propagating microwaves in a transmission line could be controlled by different frequency single photons in a resonator.

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Z. H. Peng, J. H. Ding, Y. Zhou, L. L. Ying, Z. Wang, L. Zhou, L. M. Kuang, Yu-xi Liu, O. Astafiev, J. S. Tsai. 2018-01-05. Vacuum-induced Autler-Townes splitting in a superconducting artificial atom. https://doi.org/10.1103/physreva.97.063809

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