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A widely tunable parametric amplifier based on a SQUID array resonator

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 نشر من قبل Manuel Castellanos Beltran
 تاريخ النشر 2007
  مجال البحث فيزياء
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We create a Josephson parametric amplifier from a transmission line resonator whose inner conductor is made from a series SQUID array. By changing the magnetic flux through the SQUID loops, we are able to adjust the circuits resonance frequency and, consenquently, the center of the amplified band, between 4 and 7.8 GHz. We observe that the amplifier has gains as large as 28 dB and infer that it adds less than twice the input vacuum noise.



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