Condensed Matter Seminars

The use of hydrogen to modify the electronic structure in magnetic thin films and heterostructures has opened new routes to tailor magnetic interactions in materials. Hydrogen can, for example, be used to control the strength and character of magnetic interactions. For example, the switching from antiferromagnetic to ferromagnetic order, and vice versa, has been demonstrated for exchange coupled magnetic superlattices. As the sign of the interlayer exchange coupling (J) can be switched by the insertion of hydrogen, J´ arbitrarily close to zero must be accessible. When the exchange interaction between adjacent magnetic layers is completely suppressed, the heterostructure can then be taken to consist of a collection of quasi two-dimensional magnetic sheets, when the ferromagnetic layers are very thin. Consequently, the introduction of hydrogen can be viewed as a route to tune the dimensionality of these structures.