Magnetic yttrium alloys

Permanent magnets having properties several times superior to any other known materials were developed in 1967. Praseodymium, yttrium, samarium, lanthanum, and cerium are alloyed with cobalt in the range... 

The existence of such a long-range ordered magnetic structure down to at least 1.5 atom% Gd in FGd alloys implies a driving mechanism due to the electronic structure of the yttrium matrix. It has been proposed (Sarkissian and Coles 1976, Wenger and Mydosh 1984b) that the rare-earth moments stabilize the spin density wave (SDW) (Overhauser 1959, 1960) in the matrix. A somewhat different... 

The magnetic lanthanide ion is typically introduced as an impurity into a host crystal which may be non-metallic or metallic. In many cases the lanthanide ion replaces an inert yttrium or lanthanum ion in a compound or alloy, or alternatively the yttrium or lanthanum may be regarded as diluting the magnetic lanthanide species in a compound of the latter. In other cases, the lanthanide ion is substituted into an altogether different crystal lattice, as for example into NaCl, CaFi, or into a metal such as silver. 

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