Устойчивость топологически защищенных магнитных структур для устройств компьютерной памяти

(по материалам кандидатской диссертации)

Докладчица: Поткина Мария Николаевна, аспирантка 4-го года обучения кафедры статистической физики

Дата, время и место: 19 марта 2021 г., 17:20, онлайн (MS Teams)


Разработаны методы, алгоритмы и программы для количественной оценки устойчивости двумерных топологических магнитных структур относительно тепловых флуктуаций и случайных внешних воздействий. Выполнены расчеты времен жизни магнитных состояний таких систем при произвольных температурах с учетом  влияния границ образца, магнитных примесей, структурных дефектов, внешнего магнитного поля. Исследуемые  структуры, в частности скирмионы в магнитных системах со взаимодействием Дзялошинского–Мории — одни из наиболее перспективных кандидатов для создания сверхплотной, быстрой и энергоэфективной магнитной памяти.

Публикации по теме диссертации:
  1. V.M. Uzdin, M.N. Potkina, I.S. Lobanov, P.F. Bessarab, H. Jónsson, The effect of confinement and defects on the thermal stability of skyrmions, Physica B, 549, 6–9 (2018), DOI: 10.1016/j.physb.2017.09.040 🔗
  2. V.M. Uzdin, M.N. Potkina, I.S. Lobanov, P.F. Bessarab, H. Jónsson, Energy surface and lifetime of magnetic skyrmions, Journal of Magnetism and Magnetic Materials, 459, 236–240 (2018), DOI: 10.1016/j.jmmm.2017.10.100 🔗
  3. I.S. Lobanov, M.N. Potkina, H. Jónsson, V.M. Uzdin, Truncated minimum energy path method for finding first order saddle points, Nanosystems: Physics, Chemistry, Mathematics. 8 (5), p. 586–595 (2017), DOI: 10.17586/2220-8054-2017-8-5-586-595 🔗
  4. A.S. Varentsova, M.N. Potkina, S. von Malottki, S. Heinze, P.F. Bessarab, Interplay between size and stability of magnetic skyrmions, Nanosystems: Physics, Chemistry, Mathematics. 9 (3), p. 356–363 (2018), DOI: 10.17586/2220-8054-2018-9-3-356-363 🔗
  5. K.S. Denisov, I.V. Rozhansky, M.N. Potkina, I.S. Lobanov, E. Lähderanta, and V.M. Uzdin, Topological Hall effect for electron scattering on nanoscale skyrmions in external magnetic field, Physical Review B, 98, 214407 (2018), DOI: 10.1103/PhysRevB.98.214407 🔗
  6. S.M. Vlasov, P.F. Bessarab, I.S. Lobanov, M.N. Potkina, V.M. Uzdin, H. Jónsson, Magnetic skyrmion annihilation by quantum mechanical tunneling, New Journal of Physics, 22, 083013 (2020), DOI: 10.1088/1367-2630/ab9f6d 🔗
  7. Anastasiia S. Varentcova, Stephan von Malottki, Maria N. Potkina, Grzegorz Kwiatkowski, Stefan Heinze, Pavel F. Bessarab, Towards room temperature nanoscale skyrmions in ultrathin films, npj Comput Mater 6, 193 (2020), DOI: 10.1038/s41524-020-00453-w 🔗
  8. M.N. Potkina, I.S. Lobanov, V.M. Uzdin, Nonmagnetic impurities in skyrmion racetrack memory, Nanosystems: Physics, Chemistry, Mathematics. 11 (6), p. 628–635 (2020), DOI: 10.17586/2220-8054-2020-11-6-628-635 🔗
  9. M.N. Potkina, I.S. Lobanov, V.M. Uzdin, Fine energy structure of a magnetic skyrmion localized on a nonmagnetic impurity in an external magnetic field, Physics of Complex Systems, 1, 4 (2020). DOI: 10.33910/2687-153X-2020-1-4-165-168 🔗

Stability of topologically protected magnetic structures for computer memory applications

(based on the materials of the Ph.D. thesis)

Speaker: Maria N. Potkina, Ph.D. graduate student of the Department of statistical physics

Date, time and venue: March 19, 2021, 5:20 PM, online (MS Teams)


Methods, algorithms and programs for quantitative estimation of the stability of two-dimensional topological magnetic structures with respect to thermal fluctuations and random perturbations have been developed. Calculations of the lifetimes of magnetic states of such systems at arbitrary temperatures, are performed taking into account the influence of sample boundaries, magnetic impurities, structural defects, and variation of an external magnetic field. The structures under investigation, in particular skyrmions in magnetic systems with the Dzyaloshinskii–Moriya interaction, are promising candidates for creating superdense, fast, and energy-efficient magnetic memory.

Publications:
  1. V.M. Uzdin, M.N. Potkina, I.S. Lobanov, P.F. Bessarab, H. Jónsson, The effect of confinement and defects on the thermal stability of skyrmions, Physica B, 549, 6–9 (2018), DOI: 10.1016/j.physb.2017.09.040 🔗
  2. V.M. Uzdin, M.N. Potkina, I.S. Lobanov, P.F. Bessarab, H. Jónsson, Energy surface and lifetime of magnetic skyrmions, Journal of Magnetism and Magnetic Materials, 459, 236–240 (2018), DOI: 10.1016/j.jmmm.2017.10.100 🔗
  3. I.S. Lobanov, M.N. Potkina, H. Jónsson, V.M. Uzdin, Truncated minimum energy path method for finding first order saddle points, Nanosystems: Physics, Chemistry, Mathematics. 8 (5), p. 586–595 (2017), DOI: 10.17586/2220-8054-2017-8-5-586-595 🔗
  4. A.S. Varentsova, M.N. Potkina, S. von Malottki, S. Heinze, P.F. Bessarab, Interplay between size and stability of magnetic skyrmions, Nanosystems: Physics, Chemistry, Mathematics. 9 (3), p. 356–363 (2018), DOI: 10.17586/2220-8054-2018-9-3-356-363 🔗
  5. K.S. Denisov, I.V. Rozhansky, M.N. Potkina, I.S. Lobanov, E. Lähderanta, and V.M. Uzdin, Topological Hall effect for electron scattering on nanoscale skyrmions in external magnetic field, Physical Review B, 98, 214407 (2018), DOI: 10.1103/PhysRevB.98.214407 🔗
  6. S.M. Vlasov, P.F. Bessarab, I.S. Lobanov, M.N. Potkina, V.M. Uzdin, H. Jónsson, Magnetic skyrmion annihilation by quantum mechanical tunneling, New Journal of Physics, 22, 083013 (2020), DOI: 10.1088/1367-2630/ab9f6d 🔗
  7. Anastasiia S. Varentcova, Stephan von Malottki, Maria N. Potkina, Grzegorz Kwiatkowski, Stefan Heinze, Pavel F. Bessarab, Towards room temperature nanoscale skyrmions in ultrathin films, npj Comput Mater 6, 193 (2020), DOI: 10.1038/s41524-020-00453-w 🔗
  8. M.N. Potkina, I.S. Lobanov, V.M. Uzdin, Nonmagnetic impurities in skyrmion racetrack memory, Nanosystems: Physics, Chemistry, Mathematics. 11 (6), p. 628–635 (2020), DOI: 10.17586/2220-8054-2020-11-6-628-635 🔗
  9. M.N. Potkina, I.S. Lobanov, V.M. Uzdin, Fine energy structure of a magnetic skyrmion localized on a nonmagnetic impurity in an external magnetic field, Physics of Complex Systems, 1, 4 (2020). DOI: 10.33910/2687-153X-2020-1-4-165-168 🔗