Phase transition in ising magnetic superlattice nanowires: Molecular field theory approach

Within the framework of the molecular-field theory approach, (I,r) hexagonal magnetic superlattice nanowire model in which the I atomic layers of material a alternate with r atomic layers of material b is considered. These materials may be both ferromagnetic and antiferromagnetic. The transition temperature T-c for the nanowires is calculated as a function of inter-and intralayer exchange constant by the transfer matrix method. In particular case, the results are presented for the (1,1), (2,1), (2,2), (3,1), (4,1) and (4,2) ferromagnetic superlattice nanowires. It has been determined that critical temperature increases with the layer number in one elementary unit cell increases and it decrease when the difference of numbers of atomic layers, belonging to deferent materials, increases. (C) 2015 Elsevier B.V. All rights reserved.