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Controlling the spontaneous emission of a superconducting transmon qubit

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 نشر من قبل Andrew Houck
 تاريخ النشر 2008
  مجال البحث فيزياء
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We present a detailed characterization of coherence in seven transmon qubits in a circuit QED architecture. We find that spontaneous emission rates are strongly influenced by far off-resonant modes of the cavity and can be understood within a semiclassical circuit model. A careful analysis of the spontaneous qubit decay into a microwave transmission-line cavity can accurately predict the qubit lifetimes over two orders of magnitude in time and more than an octave in frequency. Coherence times $T_1$ and $T_2^*$ of more than a microsecond are reproducibly demonstrated.



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