najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМОnajo-1065Research ArticlePHYSICSФИЗИКАNavigation on the energy surface of the noncollinear Alexander-Anderson modelNavigation on the energy surface of the noncollinear Alexander-Anderson modelBessarabP. F.BessarabP. F.

Stockholm; Россия; St. Petersburg

Stockholm; St. Petersburg

bessarab@kth.seSkorodumovA.SkorodumovA.

St. Petersburg

St. Petersburg

skorodumov@vingrad.ruUzdinV. M.UzdinV. M.

St. Petersburg

St. Petersburg

v.uzdin@mail.ruJ´onssonH.J´onssonH.

Reykjav´ık; Финляндия; Espoo

Reykjav´ık; Finland; Espoo

hj@hi.isRoyal Institute of Technology KTH; St. Petersburg State UniversityШвецияRoyal Institute of Technology KTH; St. Petersburg State UniversitySwedenITMO UniversityРоссияITMO UniversityRussian FederationSt. Petersburg State University; ITMO UniversityРоссияSt. Petersburg State University; ITMO UniversityRussian FederationUniversity of Iceland; Aalto UniversityИсландияUniversity of Iceland; Aalto UniversityIceland20141708202556757781Copyright © Bessarab P.F., Skorodumov A., Uzdin V.M., J´onsson H., 20252025Bessarab P.F., Skorodumov A., Uzdin V.M., J´onsson H.Bessarab P.F., Skorodumov A., Uzdin V.M., J´onsson H.This work is licensed under a Creative Commons Attribution 4.0 License.https://nanojournal.ifmo.ru/jour/article/view/1065

   Implementation of the multiple impurity, noncollinear Alexander-Anderson model is described in detail and an analytical expression given for the force which determines the orientation of the magnetic momenta as well as a corresponding magnetic force theorem. Applications to trimers of Cr, Mn and Fe adsorbed on a metal surface are described, including the energy surface as a function of the the angles specifying the orientation of the magnetic momenta and minimum energy paths for transitions between stable states, which necessarily involve noncollinear ordering. A simple model for the interaction of a magnetic STM tip with a Cr dimer on a surface is briefly described. A finite range approximation is also formulated, which simplifies the self-consistency calculations and results in linear scaling of the computational effort with the number of magnetic atoms in the system. The theoretical approach described here can be used to study magnetic systems with complex energy landscapes, including stable states and magnetic transitions in frustrated magnetic systems, over a range in length scale, from a few to several thousands of magnetic atoms.

   Implementation of the multiple impurity, noncollinear Alexander-Anderson model is described in detail and an analytical expression given for the force which determines the orientation of the magnetic momenta as well as a corresponding magnetic force theorem. Applications to trimers of Cr, Mn and Fe adsorbed on a metal surface are described, including the energy surface as a function of the the angles specifying the orientation of the magnetic momenta and minimum energy paths for transitions between stable states, which necessarily involve noncollinear ordering. A simple model for the interaction of a magnetic STM tip with a Cr dimer on a surface is briefly described. A finite range approximation is also formulated, which simplifies the self-consistency calculations and results in linear scaling of the computational effort with the number of magnetic atoms in the system. The theoretical approach described here can be used to study magnetic systems with complex energy landscapes, including stable states and magnetic transitions in frustrated magnetic systems, over a range in length scale, from a few to several thousands of magnetic atoms.

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The authors declare that there are no conflicts of interest present.