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Fletta eftir höfundi "Bessarab, Pavel"

Fletta eftir höfundi "Bessarab, Pavel"

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  • Nosikov, I.A.; Klimenko, M.V.; Bessarab, Pavel; Zhbankov, G.A (Elsevier BV, 2017-07)
    Point-to-point ray tracing is an important problem in many fields of science. While direct variational methods where some trajectory is transformed to an optimal one are routinely used in calculations of pathways of seismic waves, chemical reactions, ...
  • Bessarab, Pavel (American Physical Society (APS), 2017-04-24)
    Rohart et al. [Phys. Rev. B 93, 214412 (2016)] recently reported calculations indicating two mechanisms for the annihilation of a skyrmion in a Co monolayer on Pt(111). The path calculations were based on a method presented in the Supplemental Material ...
  • Müller, Gideon Philipp; Bessarab, Pavel; Vlasov, Sergei M.; Lux, Fabian; Kiselev, Nikolai S.; Blügel, Stefan; Uzdin, Valery M.; Jónsson, Hannes (American Physical Society (APS), 2018-11-06)
    Various transitions that a magnetic Skyrmion can undergo are found in calculations using a method for climbing up the energy surface and converging onto first order saddle points. In addition to collapse and escape through a boundary, the method ...
  • Uzdin, Valery M.; Potkina, Maria; Lobanov, Igor S.; Bessarab, Pavel; Jónsson, Hannes (Elsevier BV, 2017-09)
    The stability of magnetic skyrmions against thermal fluctuations and external perturbations is investigated within the framework of harmonic transition state theory for magnetic degrees of freedom. The influence of confined geometry and atomic scale ...
  • Schrautzer, Hendrik; von Malottki, Stephan; Heinze, Stefan; Bessarab, Pavel (American Physical Society (APS), 2022-01-11)
    Theoretical calculations of thermally activated decay of skyrmions in systems comprising several magnetic monolayers are presented, with a special focus on bilayer systems. Mechanisms of skyrmion collapse are identified and corresponding energy barriers ...
  • Uzdin, V.M.; Potkina, M.N.; Lobanov, I.S.; Bessarab, Pavel; Jónsson, Hannes (Elsevier BV, 2017-11)
    The stability of skyrmions in various environments is estimated by analyzing the multidimensional surface describing the energy of the system as a function of the directions of the magnetic moments in the system. The energy is given by a Heisenberg-like ...
  • von Malottki, S.; Dupé, B.; Bessarab, Pavel; Delin, A.; Heinze, S. (Springer Nature, 2017-09-26)
    Skyrmions are localized, topologically non-trivial spin structures which have raised high hopes for future spintronic applications. A key issue is skyrmion stability with respect to annihilation into the ferromagnetic state. Energy barriers for this ...
  • Muckel, Florian; von Malottki, Stephan; Holl, Christian; Pestka, Benjamin; Pratzer, Marco; Bessarab, Pavel; Heinze, Stefan; Morgenstern, Markus (Springer Nature, 2021-01-04)
    Magnetic skyrmions are key candidates for applications in memory, logic and neuromorphic computing. An essential property is their topological protection that is caused by the swirling spin texture and described by a robust integer winding number. ...
  • Haldar, Soumyajyoti; von Malottki, Stephan; Meyer, Sebastian; Bessarab, Pavel; Heinze, Stefan (American Physical Society (APS), 2018-08-27)
    We show that stable skyrmions with diameters of a few nanometers can emerge in atomic Pd/Fe bilayers on the Rh(111) surface. Based on density functional theory we calculate the exchange and the Dzyaloshinskii-Moriya interaction as well as the ...
  • Nosikov, Igor; Klimenko, Maxim; Zhbankov, Gennady; Podlesnyi, Aleksey; Ivanova, Vera; Bessarab, Pavel (IEEE, 2019-09-09)
    A variant of the direct optimization method for point-to-point ionospheric ray tracing is presented. The method is well suited for applications where the launch direction of the radio wave ray is unknown, but the position of the receiver is specified ...
  • Varentsova, A.S.; Potkina, Maria; von Malottki, S.; Heinze, S.; Bessarab, Pavel (ITMO University, 2018-06-24)
    The relationship between the size and stability of isolated skyrmions in a magnetic monolayer is analyzed based on minimum energy path calculations and atomistic spin Hamiltonian. It is demonstrated that the energy barrier protecting the skyrmion from ...
  • Bessarab, Pavel; Müller, Gideon Philipp; Lobanov, Igor S.; Rybakov, Filipp N.; Kiselev, Nikolai S.; Jónsson, Hannes; Uzdin, Valery M.; Blügel, Stefan; Bergqvist, Lars; Delin, Anna (Springer Nature, 2018-02-21)
    The skyrmion racetrack is a promising concept for future information technology. There, binary bits are carried by nanoscale spin swirls–skyrmions–driven along magnetic strips. Stability of the skyrmions is a critical issue for realising this technology. ...
  • Fransson, J.; Thonig, D.; Bessarab, Pavel; Bhattacharjee, S.; Hellsvik, J.; Nordström, L. (American Physical Society (APS), 2017-12-13)
    A coupled atomistic spin and lattice dynamics approach is developed which merges the dynamics of these two degrees of freedom into a single set of coupled equations of motion. The underlying microscopic model comprises local exchange interactions between ...
  • Kwiatkowski, Grzegorz J.; Badarneh, Mohammad H. A.; Berkov, Dmitry V.; Bessarab, Pavel (American Physical Society (APS), 2021-04-29)
    A complete analytical solution to the optimal reversal of a macrospin with easy-axis anisotropy is presented. An optimal control path minimizing the energy cost of the reversal is identified and used to derive the time-dependent direction and amplitude ...
  • Vlasov, Sergei M.; Kwiatkowski, Grzegorz J.; Lobanov, Igor S.; Uzdin, Valery M.; Bessarab, Pavel (American Physical Society (APS), 2022-04-07)
    It is demonstrated by means of the optimal control theory that the energy cost of the spin-orbit torque induced reversal of a nanomagnet with perpendicular anisotropy can be strongly reduced by proper shaping of both in-plane components of the current ...
  • von Malottki, Stephan; Haldar, Soumyajyoti; Delin, Anna; Heinze, Stefan; Bessarab, Pavel (American Physical Society (APS), 2019-02-26)
    We show that thermal stability of skyrmions due to entropic effects can be strongly affected by external control parameters such as magnetic field and interface composition. The lifetimes of isolated skyrmions in atomic Pd/Fe bilayers on Ir(111) and ...
  • Bergman, Anders; Hellsvik, Johan; Bessarab, Pavel; Delin, Anna (Springer Nature, 2016-11-14)
    Recent experimental data demonstrate emerging magnetic order in platinum atomically thin nanowires. Furthermore, an unusual form of magnetic anisotropy – colossal magnetic anisotropy (CMA) – was earlier predicted to exist in atomically thin platinum ...
  • Bessarab, Pavel; Yudin, D.; Gulevich, D. R.; Wadley, P.; Titov, M.; Tretiakov, Oleg A. (American Physical Society (APS), 2019-04-26)
    The two-dimensional Heisenberg exchange model with out-of-plane anisotropy and a Dzyaloshinskii-Moriya interaction is employed to investigate the lifetime and stability of antiferromagnetic (AFM) skyrmion as a function of temperature and external ...
  • Szilva, A.; Thonig, D.; Bessarab, Pavel; Kvashnin, Y. O.; Rodrigues, D. C. M.; Cardias, R.; Pereiro, M.; Nordström, L.; Bergman, A.; Klautau, A. B.; Eriksson, O. (American Physical Society (APS), 2017-10-10)
    We show for a simple noncollinear configuration of the atomistic spins (in particular, where one spin is rotated by a finite angle in a ferromagnetic background) that the pairwise energy variation computed in terms of multiple-scattering formalism ...