<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.3 20210610//EN" "JATS-journalpublishing1-3.dtd">
<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">najo</journal-id><journal-title-group><journal-title xml:lang="en">Nanosystems: Physics, Chemistry, Mathematics</journal-title><trans-title-group xml:lang="ru"><trans-title>Наносистемы: физика, химия, математика</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2220-8054</issn><issn pub-type="epub">2305-7971</issn><publisher><publisher-name>Университет ИТМО</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.17586/2220-8054-2021-12-1-5-14</article-id><article-id custom-type="elpub" pub-id-type="custom">najo-348</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>MATHEMATICS</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>МАТЕМАТИКА</subject></subj-group></article-categories><title-group><article-title>Bifurcating standing waves for effective equations in gapped honeycomb structures</article-title><trans-title-group xml:lang="ru"><trans-title>Расщепляющиеся стоячие волны для эффективных уравнений в гексагональных структурах с зазорами</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Borrelli</surname><given-names>W.</given-names></name><name name-style="western" xml:lang="en"><surname>Borrelli</surname><given-names>W.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Piazza dei Cavalieri 3, I-56100, Pisa</p></bio><bio xml:lang="en"><p>Piazza dei Cavalieri 3, I-56100, Pisa</p></bio><email xlink:type="simple">william.borrelli@sns.it</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Carlone</surname><given-names>R.</given-names></name><name name-style="western" xml:lang="en"><surname>Carlone</surname><given-names>R.</given-names></name></name-alternatives><bio xml:lang="ru"><p>MSA, via Cinthia, I-80126, Napoli</p></bio><bio xml:lang="en"><p>MSA, via Cinthia, I-80126, Napoli</p></bio><email xlink:type="simple">raffaele.carlone@unina.it</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Centro De Giorgi, Scuola Normale Superiore</institution></aff><aff xml:lang="en"><institution>Centro De Giorgi, Scuola Normale Superiore</institution></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Universita “Federico II” di Napoli, Dipartimento di Matematica e Applicazioni “R. Caccioppoli”</institution></aff><aff xml:lang="en"><institution>Universita “Federico II” di Napoli, Dipartimento di Matematica e Applicazioni “R. Caccioppoli”</institution></aff></aff-alternatives><pub-date pub-type="collection"><year>2021</year></pub-date><pub-date pub-type="epub"><day>28</day><month>07</month><year>2025</year></pub-date><volume>12</volume><issue>1</issue><fpage>5</fpage><lpage>14</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Borrelli W., Carlone R., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Borrelli W., Carlone R.</copyright-holder><copyright-holder xml:lang="en">Borrelli W., Carlone R.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://nanojournal.ifmo.ru/jour/article/view/348">https://nanojournal.ifmo.ru/jour/article/view/348</self-uri><abstract><p>In this paper, we deal with two-dimensional cubic Dirac equations, appearing as an effective model in gapped honeycomb structures. We give a formal derivation starting from cubic Schrodinger equations and prove the existence of standing waves bifurcating from one band-edge of the linear spectrum.</p></abstract><trans-abstract xml:lang="ru"><p>В этой статье мы имеем дело с двумерными кубическими уравнениями Дирака, выступающими в качестве эффективной модели в гексагональных структурах с зазорами. Мы даем формальный вывод, исходя из кубических уравнений Шредингера, и доказываем существование стоячих волн, ответвляющихся от одного края полосы линейного спектра.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>нелинейные уравнения Дирака</kwd><kwd>бифуркационные методы</kwd><kwd>теоремы существования</kwd><kwd>гексагональные структуры</kwd></kwd-group><kwd-group xml:lang="en"><kwd>nonlinear Dirac equations</kwd><kwd>bifurcation methods</kwd><kwd>existence results</kwd><kwd>honeycomb structures</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Fefferman C.L., Weinstein M.I. Honeycomb lattice potentials and dirac points. J. Amer. Math. Soc., 2012, 25, P. 1169-1220.</mixed-citation><mixed-citation xml:lang="en">Fefferman C.L., Weinstein M.I. Honeycomb lattice potentials and dirac points. J. Amer. Math. Soc., 2012, 25, P. 1169-1220.</mixed-citation></citation-alternatives></ref><ref id="cit2"><label>2</label><citation-alternatives><mixed-citation xml:lang="ru">Fefferman C.L., Weinstein M.I. Wave packets in honeycomb structures and two-dimensional Dirac equations. Comm. Math. Phys., 2014, 326, P. 251-286.</mixed-citation><mixed-citation xml:lang="en">Fefferman C.L., Weinstein M.I. Wave packets in honeycomb structures and two-dimensional Dirac equations. Comm. Math. Phys., 2014, 326, P. 251-286.</mixed-citation></citation-alternatives></ref><ref id="cit3"><label>3</label><citation-alternatives><mixed-citation xml:lang="ru">Erdös L., Schlein B., Yau H.-T. Derivation of the cubic non-linear Schrodinger equation from quantum dynamics of many-body systems. Invent. Math., 2007, 167, P. 515-614.</mixed-citation><mixed-citation xml:lang="en">Erdös L., Schlein B., Yau H.-T. Derivation of the cubic non-linear Schrodinger equation from quantum dynamics of many-body systems. Invent. Math., 2007, 167, P. 515-614.</mixed-citation></citation-alternatives></ref><ref id="cit4"><label>4</label><citation-alternatives><mixed-citation xml:lang="ru">Moloney J., Newell A. Nonlinear optics. Westview Press, Advanced Book Program, Boulder, CO, 2004.</mixed-citation><mixed-citation xml:lang="en">Moloney J., Newell A. Nonlinear optics. Westview Press, Advanced Book Program, Boulder, CO, 2004.</mixed-citation></citation-alternatives></ref><ref id="cit5"><label>5</label><citation-alternatives><mixed-citation xml:lang="ru">Pitaevskii L., Stringari S. Bose-Einstein condensation. International Series of Monographs on Physics, The Clarendon Press, Oxford University Press, Oxford, 2003,116.</mixed-citation><mixed-citation xml:lang="en">Pitaevskii L., Stringari S. Bose-Einstein condensation. International Series of Monographs on Physics, The Clarendon Press, Oxford University Press, Oxford, 2003,116.</mixed-citation></citation-alternatives></ref><ref id="cit6"><label>6</label><citation-alternatives><mixed-citation xml:lang="ru">Fefferman C.L., Weinstein M.I. Waves in honeycomb structures. Journ 'ees 'equations aux d 'eriv 'eespartielles, 2012, 12, 12 p.</mixed-citation><mixed-citation xml:lang="en">Fefferman C.L., Weinstein M.I. Waves in honeycomb structures. Journ 'ees 'equations aux d 'eriv 'eespartielles, 2012, 12, 12 p.</mixed-citation></citation-alternatives></ref><ref id="cit7"><label>7</label><citation-alternatives><mixed-citation xml:lang="ru">Arbunich J., Sparber C. Rigorous derivation of nonlinear Dirac equations for wave propagation in honeycomb structures. J. Math. Phys., 2018, 59,011509.</mixed-citation><mixed-citation xml:lang="en">Arbunich J., Sparber C. Rigorous derivation of nonlinear Dirac equations for wave propagation in honeycomb structures. J. Math. Phys., 2018, 59,011509.</mixed-citation></citation-alternatives></ref><ref id="cit8"><label>8</label><citation-alternatives><mixed-citation xml:lang="ru">Borrelli W. Weakly localized states for nonlinear Dirac equations. Calc. Var. Partial Differential Equations, 2018, 57, P. 57-155.</mixed-citation><mixed-citation xml:lang="en">Borrelli W. Weakly localized states for nonlinear Dirac equations. Calc. Var. Partial Differential Equations, 2018, 57, P. 57-155.</mixed-citation></citation-alternatives></ref><ref id="cit9"><label>9</label><citation-alternatives><mixed-citation xml:lang="ru">Borrelli W., Frank R.L. Sharp decay estimates for critical Dirac equations. Trans. Amer. Math. Soc., 2020, 373, P. 2045-2070.</mixed-citation><mixed-citation xml:lang="en">Borrelli W., Frank R.L. Sharp decay estimates for critical Dirac equations. Trans. Amer. Math. Soc., 2020, 373, P. 2045-2070.</mixed-citation></citation-alternatives></ref><ref id="cit10"><label>10</label><citation-alternatives><mixed-citation xml:lang="ru">Borrelli W. Stationary solutions for the 2D critical Dirac equation with Kerr nonlinearity. J. Differential Equations, 2017, 263, P. 7941-7964.</mixed-citation><mixed-citation xml:lang="en">Borrelli W. Stationary solutions for the 2D critical Dirac equation with Kerr nonlinearity. J. Differential Equations, 2017, 263, P. 7941-7964.</mixed-citation></citation-alternatives></ref><ref id="cit11"><label>11</label><citation-alternatives><mixed-citation xml:lang="ru">Borrelli W. Symmetric solutions for a 2D critical Dirac equation. ArXiv e-prints, 2020, arXiv:2010.04630.</mixed-citation><mixed-citation xml:lang="en">Borrelli W. Symmetric solutions for a 2D critical Dirac equation. ArXiv e-prints, 2020, arXiv:2010.04630.</mixed-citation></citation-alternatives></ref><ref id="cit12"><label>12</label><citation-alternatives><mixed-citation xml:lang="ru">Ammann B., Grosjean J.-F., Humbert E., Morel B. A spinorial analogue of Aubin's inequality. Math. Z., 2008, 260, P. 127-151.</mixed-citation><mixed-citation xml:lang="en">Ammann B., Grosjean J.-F., Humbert E., Morel B. A spinorial analogue of Aubin's inequality. Math. Z., 2008, 260, P. 127-151.</mixed-citation></citation-alternatives></ref><ref id="cit13"><label>13</label><citation-alternatives><mixed-citation xml:lang="ru">Grosse N. On a conformal invariant of the Dirac operator on noncompact manifolds. Ann. Global Anal. Geom., 2006, 30, P. 407-416.</mixed-citation><mixed-citation xml:lang="en">Grosse N. On a conformal invariant of the Dirac operator on noncompact manifolds. Ann. Global Anal. Geom., 2006, 30, P. 407-416.</mixed-citation></citation-alternatives></ref><ref id="cit14"><label>14</label><citation-alternatives><mixed-citation xml:lang="ru">Isobe T. Nonlinear Dirac equations with critical nonlinearities on compact Spin manifolds. J. Funct. Anal., 2011, 260, P. 253-307.</mixed-citation><mixed-citation xml:lang="en">Isobe T. Nonlinear Dirac equations with critical nonlinearities on compact Spin manifolds. J. Funct. Anal., 2011, 260, P. 253-307.</mixed-citation></citation-alternatives></ref><ref id="cit15"><label>15</label><citation-alternatives><mixed-citation xml:lang="ru">Maalaoui A. Infinitely many solutions for the spinorial Yamabe problem on the round sphere. Nonlinear Differential Equations Appl. NoDEA, 2016, 23, 25.</mixed-citation><mixed-citation xml:lang="en">Maalaoui A. Infinitely many solutions for the spinorial Yamabe problem on the round sphere. Nonlinear Differential Equations Appl. NoDEA, 2016, 23, 25.</mixed-citation></citation-alternatives></ref><ref id="cit16"><label>16</label><citation-alternatives><mixed-citation xml:lang="ru">Borrelli W., Maalaoui A. Some properties of Dirac-Einstein bubbles. J. Geometric Analysis, 2020, https://doi.org/10.1007/s12220-020-00503-1.</mixed-citation><mixed-citation xml:lang="en">Borrelli W., Maalaoui A. Some properties of Dirac-Einstein bubbles. J. Geometric Analysis, 2020, https://doi.org/10.1007/s12220-020-00503-1.</mixed-citation></citation-alternatives></ref><ref id="cit17"><label>17</label><citation-alternatives><mixed-citation xml:lang="ru">Maalaoui A., Martino V. Characterization of the Palais-Smale sequences for the conformal Dirac-Einstein problem and applications. J. Differential Equations, 2019, 266, P. 2493-2541.</mixed-citation><mixed-citation xml:lang="en">Maalaoui A., Martino V. Characterization of the Palais-Smale sequences for the conformal Dirac-Einstein problem and applications. J. Differential Equations, 2019, 266, P. 2493-2541.</mixed-citation></citation-alternatives></ref><ref id="cit18"><label>18</label><citation-alternatives><mixed-citation xml:lang="ru">Ounaies H. Perturbation method for a class of nonlinear Dirac equations. Differential Integral Equations, 2000, 13, P. 707-720.</mixed-citation><mixed-citation xml:lang="en">Ounaies H. Perturbation method for a class of nonlinear Dirac equations. Differential Integral Equations, 2000, 13, P. 707-720.</mixed-citation></citation-alternatives></ref><ref id="cit19"><label>19</label><citation-alternatives><mixed-citation xml:lang="ru">Borrelli W., Carlone R., Tentarelli L. On the nonlinear Dirac equation on noncompact metric graphs. Journal of Differential Equations, 2021, 278, P. 326-357.</mixed-citation><mixed-citation xml:lang="en">Borrelli W., Carlone R., Tentarelli L. On the nonlinear Dirac equation on noncompact metric graphs. Journal of Differential Equations, 2021, 278, P. 326-357.</mixed-citation></citation-alternatives></ref><ref id="cit20"><label>20</label><citation-alternatives><mixed-citation xml:lang="ru">Cazenave T., V'azquez L. Existence of localized solutions for a classical nonlinear Dirac field, Comm. Math. Phys., 1986,105, P. 35-47.</mixed-citation><mixed-citation xml:lang="en">Cazenave T., V'azquez L. Existence of localized solutions for a classical nonlinear Dirac field, Comm. Math. Phys., 1986,105, P. 35-47.</mixed-citation></citation-alternatives></ref><ref id="cit21"><label>21</label><citation-alternatives><mixed-citation xml:lang="ru">Cuevas-Maraver J., Kevrekidis P.G., et al. Stability of solitary waves and vortices in a 2D nonlinear Dirac model. Phys. Rev. Lett., 2016, 116, 214101.</mixed-citation><mixed-citation xml:lang="en">Cuevas-Maraver J., Kevrekidis P.G., et al. Stability of solitary waves and vortices in a 2D nonlinear Dirac model. Phys. Rev. Lett., 2016, 116, 214101.</mixed-citation></citation-alternatives></ref><ref id="cit22"><label>22</label><citation-alternatives><mixed-citation xml:lang="ru">Esteban M.J., S 'er'e E. Stationary states of the nonlinear Dirac equation: a variational approach. Comm. Math. Phys., 1995,171, P. 323-350.</mixed-citation><mixed-citation xml:lang="en">Esteban M.J., S 'er'e E. Stationary states of the nonlinear Dirac equation: a variational approach. Comm. Math. Phys., 1995,171, P. 323-350.</mixed-citation></citation-alternatives></ref><ref id="cit23"><label>23</label><citation-alternatives><mixed-citation xml:lang="ru">Thaller B. The Dirac equation, Texts and Monographs in Physics, Springer-Verlag, Berlin, 1992.</mixed-citation><mixed-citation xml:lang="en">Thaller B. The Dirac equation, Texts and Monographs in Physics, Springer-Verlag, Berlin, 1992.</mixed-citation></citation-alternatives></ref><ref id="cit24"><label>24</label><citation-alternatives><mixed-citation xml:lang="ru">Borrelli W. L' 'equation de Dirac en physique du solide et en optique non lin'eaire. PhD thesis, Universit'e Paris-Dauphine PSL, (2018).</mixed-citation><mixed-citation xml:lang="en">Borrelli W. L' 'equation de Dirac en physique du solide et en optique non lin'eaire. PhD thesis, Universit'e Paris-Dauphine PSL, (2018).</mixed-citation></citation-alternatives></ref><ref id="cit25"><label>25</label><citation-alternatives><mixed-citation xml:lang="ru">Peleg O., Bartal G., et al. Conical diffraction and gap solitons in honeycomb photonic lattices. Phys. Rev. Lett., 2007, 98, 103901.</mixed-citation><mixed-citation xml:lang="en">Peleg O., Bartal G., et al. Conical diffraction and gap solitons in honeycomb photonic lattices. Phys. Rev. Lett., 2007, 98, 103901.</mixed-citation></citation-alternatives></ref><ref id="cit26"><label>26</label><citation-alternatives><mixed-citation xml:lang="ru">Reed M., Simon B. Methods of modern mathematical physics. IV Analysis of operators, Academic Press [Harcourt Brace Jovanovich, Publishers], New York-London, 1978.</mixed-citation><mixed-citation xml:lang="en">Reed M., Simon B. Methods of modern mathematical physics. IV Analysis of operators, Academic Press [Harcourt Brace Jovanovich, Publishers], New York-London, 1978.</mixed-citation></citation-alternatives></ref><ref id="cit27"><label>27</label><citation-alternatives><mixed-citation xml:lang="ru">Ilan B., Weinstein M.I. Band-edge solitons, nonlinear Schrodinger/Gross-Pitaevskii equations, and effective media. Multiscale Model. Simul., 2010, 8, P. 1055-1101.</mixed-citation><mixed-citation xml:lang="en">Ilan B., Weinstein M.I. Band-edge solitons, nonlinear Schrodinger/Gross-Pitaevskii equations, and effective media. Multiscale Model. Simul., 2010, 8, P. 1055-1101.</mixed-citation></citation-alternatives></ref><ref id="cit28"><label>28</label><citation-alternatives><mixed-citation xml:lang="ru">Cazenave T. Semilinear Schrodinger equations. Courant Lecture Notes in Mathematics, New York University, Courant Institute of Mathematical Sciences, New York; American Mathematical Society, Providence, RI, 2003, 10,</mixed-citation><mixed-citation xml:lang="en">Cazenave T. Semilinear Schrodinger equations. Courant Lecture Notes in Mathematics, New York University, Courant Institute of Mathematical Sciences, New York; American Mathematical Society, Providence, RI, 2003, 10,</mixed-citation></citation-alternatives></ref><ref id="cit29"><label>29</label><citation-alternatives><mixed-citation xml:lang="ru">Chang S.-M., Gustafson S., Nakanishi K., Tsai T.-P. Spectra of linearized operators for NLS solitary waves. SIAM J. Math. Anal., 2007-2008, 39, P. 1070-1111.</mixed-citation><mixed-citation xml:lang="en">Chang S.-M., Gustafson S., Nakanishi K., Tsai T.-P. Spectra of linearized operators for NLS solitary waves. SIAM J. Math. Anal., 2007-2008, 39, P. 1070-1111.</mixed-citation></citation-alternatives></ref><ref id="cit30"><label>30</label><citation-alternatives><mixed-citation xml:lang="ru">Brezis H. Functional analysis, Sobolev spaces and partial differential equations. Universitat, Springer, New York, 2011.</mixed-citation><mixed-citation xml:lang="en">Brezis H. Functional analysis, Sobolev spaces and partial differential equations. Universitat, Springer, New York, 2011.</mixed-citation></citation-alternatives></ref></ref-list><fn-group><fn fn-type="conflict"><p>The authors declare that there are no conflicts of interest present.</p></fn></fn-group></back></article>
