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Dynamic behaviour of Josephson-junction qubits: crossover between Rabi oscillations and Landau-Zener transitions

S. N. Shevchenko·A. S. Kiyko·A. N. Omelyanchouk·W. Krech
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Abstract

We study the dynamic behaviour of a quantum two-level system with periodically varying parameters by solving the master equation for the density matrix. Two limiting cases are considered: multiphoton Rabi oscillations and Landau-Zener transitions. The approach is applied to the description of the dynamics of superconducting qubits. In particular, the case of the interferometer-type charge qubit with periodically varying parameters (gate voltage or magnetic flux) is investigated. The time-averaged energy level populations are calculated as funtions of the qubit's control parameters.

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S. N. Shevchenko, A. S. Kiyko, A. N. Omelyanchouk, W. Krech. 2004-12-21. Dynamic behaviour of Josephson-junction qubits: crossover between Rabi oscillations and Landau-Zener transitions. https://doi.org/10.1063/1.2001634

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