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<article 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" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Discrete and Continuous Models and Applied Computational Science</journal-id><journal-title-group><journal-title xml:lang="en">Discrete and Continuous Models and Applied Computational Science</journal-title><trans-title-group xml:lang="ru"><trans-title>Discrete and Continuous Models and Applied Computational Science</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2658-4670</issn><issn publication-format="electronic">2658-7149</issn><publisher><publisher-name xml:lang="en">Peoples' Friendship University of Russia named after Patrice Lumumba (RUDN University)</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">22918</article-id><article-id pub-id-type="doi">10.22363/2658-4670-2019-27-4-365-377</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Mathematical models in Physics</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Математические модели в физике</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Numerical modeling of stationary pseudospin waves on a graphene monoatomic films</article-title><trans-title-group xml:lang="ru"><trans-title>Численное моделирование стационарных псевдоспиновых волн на моноатомных плёнках графена</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Nhật</surname><given-names>Lê Anh</given-names></name><name xml:lang="ru"><surname>Ньат</surname><given-names>Ле Ань</given-names></name></name-alternatives><bio xml:lang="en"><p>PhD student of Department of Applied Probability and Informatics</p></bio><bio xml:lang="ru"><p>Кафедра прикладной информатики и теории вероятностей</p></bio><email>leanhnhat@tuyenquang.edu.vn</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Lovetskiy</surname><given-names>Konstantin P.</given-names></name><name xml:lang="ru"><surname>Ловецкий</surname><given-names>К. П.</given-names></name></name-alternatives><bio xml:lang="en"><p>Docent, PhD in Physics and Mathematics, Associate Professor at the Department of Applied Probability and Informatics</p></bio><bio xml:lang="ru"><p>Кафедра прикладной информатики и теории вероятностей</p></bio><email>lovetskiy-kp@rudn.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Sevastianov</surname><given-names>Leonid A.</given-names></name><name xml:lang="ru"><surname>Севастьянов</surname><given-names>Л. А.</given-names></name></name-alternatives><bio xml:lang="en"><p>Professor, Doctor of Sciences in Physics and Mathematics, Professor at the Department of Applied Probability and Informatics</p></bio><bio xml:lang="ru"><p>Кафедра прикладной информатики и теории вероятностей</p></bio><email>sevastianov-la@rudn.ru</email><xref ref-type="aff" rid="aff1"/><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Kulyabov</surname><given-names>Dmitry S.</given-names></name><name xml:lang="ru"><surname>Кулябов</surname><given-names>Д. С.</given-names></name></name-alternatives><bio xml:lang="en"><p>Docent, Doctor of Sciences in Physics and Mathematics, Professor at the Department of Applied Probability and Informatics</p></bio><bio xml:lang="ru"><p>Кафедра прикладной информатики и теории вероятностей</p></bio><email>kulyabov-ds@rudn.ru</email><xref ref-type="aff" rid="aff1"/><xref ref-type="aff" rid="aff3"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Peoples’ Friendship University of Russia (RUDN University)</institution></aff><aff><institution xml:lang="ru">Российский университет дружбы народов</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear Research</institution></aff><aff><institution xml:lang="ru">Лаборатория теоретической физики Объединённый институт ядерных исследований</institution></aff></aff-alternatives><aff-alternatives id="aff3"><aff><institution xml:lang="en">Laboratory of Information Technologies Joint Institute for Nuclear Research</institution></aff><aff><institution xml:lang="ru">Лаборатория информационных технологий Объединённый институт ядерных исследований</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2019-12-15" publication-format="electronic"><day>15</day><month>12</month><year>2019</year></pub-date><volume>27</volume><issue>4</issue><issue-title xml:lang="en">VOL 27, NO4 (2019)</issue-title><issue-title xml:lang="ru">ТОМ 27, №4 (2019)</issue-title><fpage>365</fpage><lpage>377</lpage><history><date date-type="received" iso-8601-date="2020-02-19"><day>19</day><month>02</month><year>2020</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2019, Nhật L.A., Lovetskiy K.P., Sevastianov L.A., Kulyabov D.S.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2019, Ньат Л.А., Ловецкий К.П., Севастьянов Л.А., Кулябов Д.С.</copyright-statement><copyright-year>2019</copyright-year><copyright-holder xml:lang="en">Nhật L.A., Lovetskiy K.P., Sevastianov L.A., Kulyabov D.S.</copyright-holder><copyright-holder xml:lang="ru">Ньат Л.А., Ловецкий К.П., Севастьянов Л.А., Кулябов Д.С.</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">http://creativecommons.org/licenses/by/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://journals.rudn.ru/miph/article/view/22918">https://journals.rudn.ru/miph/article/view/22918</self-uri><abstract xml:lang="en"><p>For the first time, the theoretical model of the spin-electron structure of a singlelayer graphene film was proposed by Wallace. The literature also describes ferromagnetism generated by none of the three common causes: impurities, defects, boundaries. We believe that the source of ferromagnetism is the spontaneous breaking of spin symmetry in a graphene film. The classical field model describing spontaneously broken symmetry is necessarily non-linear. Among non-linear models, the simplest is the well-known 4 model. We believe that, as a first approximation, we can describe with its help all the characteristics of spin waves that interest us, their spectra, and the domain structure of ferromagnetism in graphene. The model admits kink and anti-kink exact solutions and a quasiparticle breather, which we modeled numerically. We use the kink-anti-kink interaction energy obtained numerically to solve the Schrödinger equation, which simulates the quantum dynamics of breathers, which underlies the description of spin waves. The solution of the Schrödinger equation by the Ritz method leads to a generalized problem of eigenvalues and eigenvectors, the solution of which is mainly devoted to this work.</p></abstract><trans-abstract xml:lang="ru"><p>В экспериментах на однослойных графеновых плёнках наблюдается явление ферромагнетизма. При этом данный феномен не может порождаться ни одной из трёх распространённых причин: наличием примесей в графене, наличием дефектов в графене, влиянием границ однослойной графеновой плёнки. Авторы предполагают, что источником ферромагнетизма может служить спонтанное нарушение спиновой симметрии в графеновой плёнке. Классические полевые модели, описывающие спонтанное нарушение симметрии, являются нелинейными. Среди нелинейных моделей одной из простейших является широко известная 4 модель. Предполагается, что в рамках данной модели можно описать большинство интересующих нас характеристик спиновых волн, а также феномен ферромагнетизма в графене. Эта модель допускает наличие кинковых и антикинковых точных решений, а также существование квазичастицы бризер. Авторами численно промоделировано квазичастичное решение бризер. Для этого численно получена энергия взаимодействия решений типа кинк-антикинк. Эта энергия используется для численного решения уравнения Шрёдингера для спиновых волн со структурой бризеров. Методом Ритца решения уравнения Шрёдингера приводятся к обобщённой задаче на собственные значения и собственные векторы. Эта задача исследуется в данной статье.</p></trans-abstract><kwd-group xml:lang="en"><kwd>graphene</kwd><kwd>solitons</kwd><kwd>kinks</kwd><kwd>breathers</kwd><kwd>nonlinear models</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>графен</kwd><kwd>солитоны</kwd><kwd>кинки</kwd><kwd>бризеры</kwd><kwd>нелинейные модели</kwd></kwd-group><funding-group><funding-statement xml:lang="en">The reported study was funded by Russian Foundation for Basic Research (RFBR), project number 18-07-00567. The reported study was funded by Russian Foundation for Basic Research (RFBR), project number 19-01-00645.</funding-statement><funding-statement xml:lang="ru">The reported study was funded by Russian Foundation for Basic Research (RFBR), project number 18-07-00567. The reported study was funded by Russian Foundation for Basic Research (RFBR), project number 19-01-00645.</funding-statement></funding-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>J. Červenka, M. I. Katsnelson, and C. F. Flipse, “Room-temperature ferromagnetism in graphite driven by two-dimensional networks of pointdefects,” Nature Physics, vol. 5, no. 11, pp. 840-844, 2009. DOI: 10.1038/nphys1399.</mixed-citation></ref><ref id="B2"><label>2.</label><mixed-citation>Y. Wang, Y. Hoang, Y. Song, X. Zhang, Y. Ma, J. Liang, and Y. Chen, “Room-temperature ferromagnetism of graphene,” Nano Letters, vol. 9, no. 1, pp. 220-224, 2009. 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