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arXiv · 1901.10295

Time-domain grating with a periodically driven qutrit

Yingying Han·Xiao-Qing Luo·Tie-Fu Li·Wenxian Zhang·Shuai-Peng Wang·J. S. Tsai·Franco Nori·J. Q. You
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Abstract

Physical systems in the time domain may exhibit analogous phenomena in real space, such as time crystals, time-domain Fresnel lenses, and modulational interference in a qubit. Here we report the experimental realization of time-domain grating using a superconducting qutrit in periodically modulated probe and control fields via two schemes: Simultaneous modulation and complementary modulation. Both experimental and numerical results exhibit modulated Autler-Townes (AT) and modulation-induced diffraction (MID) effects. Theoretical results also confirm that the peak positions of the interference fringes of AT and MID effects are determined by the usual two-level relative phases, while the observed diffraction fringes, appearing only in the complementary modulation, are however related to the three-level relative phase. Further analysis indicates that such a single-atom time-domain diffraction originates from the correlation effect between the two time-domain gratings. Moreover, we find that the widths of the diffraction fringes are independent of the control-field power. Our results shed light on the experimental exploration of quantum coherence for modulated multi-level systems and may find promising applications in fast all-microwave switches and quantum-gate operations in the strong-driving regime.

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Yingying Han, Xiao-Qing Luo, Tie-Fu Li, Wenxian Zhang, Shuai-Peng Wang, J. S. Tsai, Franco Nori, J. Q. You. 2019-01-30. Time-domain grating with a periodically driven qutrit. https://doi.org/10.1103/physrevapplied.11.014053

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