Microwave magnetoresistance effect in a (CoFe/Cu) superlattice with micron-sized holes

The microwave giant magnetoresistance effect in a (CoFe/Cu) superlattice with micron-sized holes has been studied. Measurements of the frequency dependences of the transmission coefficient, as well as the dependences of the microwave transmission and reflection coefficients on the magnetic field, are performed. The measurements were performed on the superlattice samples without holes, having one hole with a diameter of 6.3 $\mu$m and seven holes with a diameter of 1.7 $\mu$m. It is shown that the presence of a hole with a diameter of 6.3 $\mu$m leads to a significant frequency dependence of the microwave giant magnetoresistance effect. Magnetic and magnetoresistance measurements of superlattice samples were performed.