The giant magnetoresistance effect in microwave reflection from (CoFe)/Cu superlattices

Experiments on the giant magnetoresistance effect observed in microwave reflection have been conducted in the frequency range of 26–38 GHz on (CoFe)/Cu superlattices exhibiting giant magnetoresistance. The amount of the effect has been determined (up to +3% maximum), and its magnetic field dependence has been found. The microwave reflection coefficient versus magnetic field dependence has been calculated. The measured variation of the reflection coefficient has turned out to be greater than calculated values. This discrepancy is associated with the fact that a superlattice is approximated by a homogeneous plate in calculations. The frequency dependence of the giant magnetoresistance effect in microwave reflection has been observed. It is explained by the influence of the impedance of a waveguide in which samples are placed to take measurements.