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<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.3 20210610//EN" "https://jats.nlm.nih.gov/publishing/1.3/JATS-journalpublishing1-3.dtd">
<article article-type="meeting-report" dtd-version="1.3" xml:lang="en">
  <front xmlns:xlink="http://www.w3.org/1999/xlink">
    <journal-meta>
      <journal-title-group>
        <journal-title>St. Petersburg Polytechnic University Journal: Physics and Mathematics</journal-title>
        <trans-title-group xml:lang="ru">
          <trans-title>Научно-технические ведомости СПбГПУ. Физико-математические науки</trans-title>
        </trans-title-group>
      </journal-title-group>
      <issn pub-type="epub">2304-9782, 2618-8686, 2405-7223</issn>
    </journal-meta>
    <article-meta xmlns:xlink="http://www.w3.org/1999/xlink">
      <article-id pub-id-type="publisher-id">65</article-id>
      <article-id pub-id-type="doi">10.18721/JPM.153.265</article-id>
      <title-group>
        <article-title>Application of a broadband Josephson parametric amplifier</article-title>
        <trans-title-group xml:lang="ru">
          <trans-title>Применение широкополосного джозефсоновского параметрического усилителя</trans-title>
        </trans-title-group>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Dorogov</surname>
            <given-names>Aleksandr</given-names>
          </name>
          <email>Dorogov.AE@phystech.edu</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Fedorov</surname>
            <given-names>Gleb</given-names>
          </name>
          <email>gleb.fedorov@phystech.edu</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Kalacheva</surname>
            <given-names>Daria</given-names>
          </name>
          <email>d.kalacheva@gmail.com</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Dmitriev</surname>
            <given-names>Aleksei</given-names>
          </name>
          <email>dmitrmipt@gmail.com</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Bolgar</surname>
            <given-names>Aleksey</given-names>
          </name>
          <email>alexgood@list.ru</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Abramov</surname>
            <given-names>Nikolay</given-names>
          </name>
          <email>abramov.nn@misis.ru</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Astafiev</surname>
            <given-names>Oleg</given-names>
          </name>
          <email>O.Astafiev@skoltech.ru</email>
        </contrib>
      </contrib-group>
      <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2022-12-01">
        <day>01</day>
        <month>12</month>
        <year>2022</year>
      </pub-date>
      <volume>15</volume>
      <issue>3.2</issue>
      <fpage>352</fpage>
      <lpage>357</lpage>
      <self-uri xmlns:xlink="http://www.w3.org/1999/xlink" content-type="pdf" xlink:href="https://physmath.spbstu.ru/userfiles/files/articles/2022/3.2/65_P_3_2_15_2022-352-357.pdf"/>
      <abstract xml:lang="en">
        <p>We examine the performance of a Josephson Parametric Amplifier (JPA) which uses an array of SNAILs (Superconducting Nonlinear Asymmetric Inductive eLements) as the source of nonlinearity and leverages the technique of impedance engineering (introducing a positive linear slope in the imaginary part of the input impedance seen by the SNAILs) to overcome a traditional gain-bandwidth product and increase the 1-dB compression point. We experimentally demonstrate an 18 dB gain over a 586 MHz band, along with a 1-dB compression point -101.9 dBm. All these characteristics are of great importance for the quantum devices measurements and in particular for the single-shot readout of a multi-qubit system. The signal-to-noise ratio after the application of the JPA was increased by 3 times. That led to the improvement of separation fidelity of single-shot dispersive measurements of a transmon qubit from 30.6% to 97.2%.</p>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>parametric amplifier</kwd>
        <kwd>Josephson junction</kwd>
        <kwd>gain-bandwidth product</kwd>
        <kwd>1-dB compression point</kwd>
        <kwd>single-shot readout</kwd>
      </kwd-group>
    </article-meta>
  </front>
</article>
