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

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 نشر من قبل Sergei Shevchenko N.
 تاريخ النشر 2004
  مجال البحث فيزياء
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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 qubits control parameters.



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