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Stark effect and generalized Bloch-Siegert shift in a strongly driven two-level system

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 نشر من قبل Mika Sillanpaa
 تاريخ النشر 2010
  مجال البحث فيزياء
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A superconducting qubit was driven in an ultrastrong fashion by an oscillatory microwave field, which was created by coupling via the nonlinear Josephson energy. The observed Stark shifts of the `atomic levels are so pronounced that corrections even beyond the lowest-order Bloch-Siegert shift are needed to properly explain the measurements. The quasienergies of the dressed two-level system were probed by resonant absorption via a cavity, and the results are in agreement with a calculation based on the Floquet approach.



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