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Single qubit measurements with an asymmetric single-electron transistor

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 نشر من قبل Shmuel Gurvitz
 تاريخ النشر 2004
  مجال البحث فيزياء
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We investigate qubit measurements using a single electron transistor (SET). Applying the Schrodinger equation to the entire system we find that an asymmetric SET is considerably more efficient than a symmetric SET. The asymmetric SET becomes close to an ideal detector in the large asymmetry limit. We also compared the SET detector with a point-contact detector. This comparison allows us to illuminate the relation between information gain in the measurement process and the decoherence generated by these measurement devices.



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