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<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">62</article-id>
      <article-id pub-id-type="doi">10.18721/JPM.183.162</article-id>
      <title-group>
        <article-title>Qubit-qubit entanglement in the Tavis–Cummings model with two independent resonators</article-title>
        <trans-title-group xml:lang="ru">
          <trans-title>Кубит-кубитное перепутывание в модели Тависа–Каммингса с двумя независимыми резонаторами</trans-title>
        </trans-title-group>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-1098-0300</contrib-id>
          <name>
            <surname>Bagrov</surname>
            <given-names>Alexander</given-names>
          </name>
          <email>alexander.bagrov00@mail.ru</email>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0001-8682-4956</contrib-id>
          <name>
            <surname>Bashkirov</surname>
            <given-names>Evgeniy</given-names>
          </name>
          <email>bash@ssau.ru</email>
        </contrib>
      </contrib-group>
      <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2025-12-10">
        <day>10</day>
        <month>12</month>
        <year>2025</year>
      </pub-date>
      <volume>18</volume>
      <issue>3.1</issue>
      <fpage>312</fpage>
      <lpage>316</lpage>
      <self-uri xmlns:xlink="http://www.w3.org/1999/xlink" content-type="pdf" xlink:href="https://physmath.spbstu.ru/userfiles/files/articles/2025/3.1/62_312-316_18(3_1)2025.pdf"/>
      <abstract xml:lang="en">
        <p>In this paper, a three-qubit Tavis–Cummings model with two independent lossless single-mode resonators is considered. It is assumed that the initial states of the resonator fields are thermal fields and the qubits are in genuine entangled W- and GHZ-type states. For the model under study and the specified initial states of the resonator fields and qubits, we have exactly solved the quantum Liouville equation for the full density matrix. The full density matrix was used to calculate the entanglement parameters – negativity and fidelity. The computer simulation results showed that in the investigated model, the entanglement for all initial qubit states breaks down rapidly with increasing intensity of the thermal fields of the resonators compared to the previously investigated three-qubit models. Moreover, a sudden death of entanglement is observed even for vacuum resonator fields.</p>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>independent resonators</kwd>
        <kwd>fidelity</kwd>
        <kwd>qubits</kwd>
        <kwd>negativity</kwd>
        <kwd>sudden death of entanglement</kwd>
        <kwd>single-photon transitions</kwd>
        <kwd>thermal field</kwd>
        <kwd>entanglement</kwd>
      </kwd-group>
    </article-meta>
  </front>
</article>
