Analysis of the probing field in magneto-dipolar-mode microwave microscopy

The research of chiral materials in microwaves is attractive in a lot of physical disciplines. Compared to the field of optics, where many theoretical and measurements analysis tools and techniques exist, in microwaves, the study is at its initial stages of development. Recently, microwave devices based on a ferrite disk resonator with magneto-dipolar-mode (MDM) oscillations that allow creation of near fields characterized by helical structure have been developed. These near fields, called magneto-electric (ME) fields, are essential for the chirality characterization of the sample. For effective focusing of the ME fields a special microwave device based on a metallic wire positioned above a ferrite disk was developed. Such a device allows to narrow down the effective area of the ME fields by more than an order. In this work, we show a theoretical analysis of the localized ME fields generated by a metallic wire on a ferrite disk operating as the microwave microscope. Realization of such localized ME fields is an important step in the development of a microwave sensor for effective sensing of natural and artificial enantiomeric materials.