Super Low Loss Ferrites.

The Low Temperature Transformation in Ferrites

The general behavior of majrn»!it< (iron ferrite) at its low temperature transformation (ca 1!8°K) is reviewed. One of the properties which undergoes a largr change is the magnetocrystailine snisotropy, which is larger in magnitude and has a lower symmetry below the transformation. The magnetic symmetry axis below the transition tempeiature can be predetermined by cooling a single crystal throu...

XXIst Century Ferrites

Ferrites have always been a subject of great interest from point of view of magnetic application, since the fist compass to present date. In contrast, the scientific interest for iron based magnetic oxides decreased after Ørsted discovery as they where replaces by coil as magnetizing sources. Néel discovery of ferrimagnetism boosted again interest and leads to strong developments during two dec...

Microwave Ferrites for Cryogenic Applications

Recent advances in microwave ferrite device technology have seen the introduction of superconductivity that virtually eliminates insertion losses due to electrical conduction in microstrip circuits. The conventional ferrimagnetic spinel and garnet compositions, however, are not generally optimized for temperatures in the vicinity of 77 K and may require chemical redesign in order to realize the...

Temperature dependence of core loss in cobalt substituted Ni-Zn-Cu ferrites

The temperature dependence of core loss in cobalt substituted Ni-Zn-Cu ferrites was investigated. Co ions are known to lead to a compensation of the magnetocrystalline anisotropy in Ni-Zn ferrites, at a temperature depending on the cobalt content and the Ni / Zn ratio. We observed similar behaviour in Ni-Zn-Cu and it was found that the core loss goes through a minimum around this magneto-crysta...

On Ferrites. Theory and Practise