Multi-Photon, Multi-Level Dynamics in a Superconducting Persistent-Current Qubit
نویسندگان
چکیده
Single-, two-, and three-photon transitions were driven amongst five quantum states of a niobium persistent-current qubit. A multi-level energy-band diagram was extracted using microwave spectroscopy, and avoided crossings were directly measured between the third and fourth excited states. The energy relaxation times between states connected by single-photon and multi-photon transitions were approximately 30 − 100 μs. Three-photon coherent oscillations were observed between the qubit ground and fourth excited states with a decoherence time of approximately 50 ns. PACS numbers: 03.67.Lx,03.65.Yz,85.25.Cp,85.25.Dq ∗to whom correspondance should be addressed
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