Collective effects in the 2D lattices of the magnetic nanoparticles
  The work is devoted to investigation of the collective behavior of the regular rectangular lattices of the NiFe nanoparticles caused by the dipole-dipole interaction between them. The samples was prepared by the method of the electron lithography and consist of about 100000 particles of approximately 50 nm size. The magnetization curves were investigated by the Hall magnetometry for the different orientation of the external magnetic field at 4.2K and 77K. The results points on the collective behavior of the system. The observed peculiarities we connect with the quasi-one-dimensional behavior of the system and the formation of the solitons in the system. 
A.A.Fraerman, S.A.Gusev, L.A.Mazo, I.M.Nefedov, Ju.N.Nozdrin,   M.V.Sapozhnikov, L.V.Suhodoev (Russian Academy of Science In...