INTERLAYER EXCHANGE COUPLING IN ULTRA-THIN LAYERED STRUCTURES

The strong interlayer coupling limit (perfect confinement) in ultra-thin layered magnetic structures is analysed analytically and numerically within the tight-binding model with a single electron band and in the ferromagnetic electron gas model. In the limit of ultra-thin films the coupling parameter is shown to depend significantly on the number of magnetic atomic planes. The limits of a constant chemical potential and a constant particle number are discussed and compared. The case of partial confinement and band mismatch is analysed in the ferromagnetic electron gas model. The corresponding interlayer coupling parameter decreases with decreasing degree of confinement. It also depends significantly on the band matching conditions at the interfaces between magnetic and nonmagnetic films.