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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="ru">
  <front>
    <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>
      <article-id pub-id-type="publisher-id">26</article-id>
      <article-id pub-id-type="doi">10.18721/JPM.161.226</article-id>
      <title-group>
        <article-title>Properties of the squared Laguerre–Gaussian vortices</article-title>
        <trans-title-group xml:lang="ru">
          <trans-title>Свойства квадратичных вихрей Лагерра–Гаусса</trans-title>
        </trans-title-group>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Savelyeva</surname>
            <given-names>Alexandra</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
          <email>lexis2450@gmail.com</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Kovalev</surname>
            <given-names>Alexey</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
          <email>alanko.ipsi@mail.ru</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Kozlova</surname>
            <given-names>Elena</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
          <email>kozlova.elena.s@gmail.com</email>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Kotlyar</surname>
            <given-names>Victor</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
          <email>kotlyar@ipsiras.ru</email>
        </contrib>
      </contrib-group>
      <aff id="aff1">IPSI RAS – branch of the FSRC “Crystallography and Photonics” RAS; Samara National Research University</aff>
      <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2023-05-01">
        <day>01</day>
        <month>05</month>
        <year>2023</year>
      </pub-date>
      <volume>16</volume>
      <issue>1.2</issue>
      <fpage>172</fpage>
      <lpage>178</lpage>
      <abstract xml:lang="en">
        <p>In this paper, a new type of optical vortex called the squared Laguerre–Gauss (LG)2 vortex beam has been investigated. Theoretical conclusions and numerical experiment confirm that these beams are Fourier-invariant and retain their structure at the focus of a spherical lens. In the Fresnel diffraction zone, such a beam is transformed into a superposition of conventional LG beams, the number of which is equal to the number of rings in the (LG)2 beam. The presented beams are structurally stable in the case of one intensity ring.</p>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>optical vortex</kwd>
        <kwd>topological charge</kwd>
        <kwd>Laguerre–Gauss mode</kwd>
        <kwd>Fourier invariance</kwd>
        <kwd>Fourier transform</kwd>
        <kwd>Fresnel diffraction</kwd>
      </kwd-group>
    </article-meta>
  </front>
</article>
