First Principles Study on Electronic Structure and Spontaneous Polarization of Ferrite Phase Shifter Ferroelectrics

As a device that can adjust the wave phase, the phase shifter has a wide range of applications in the field of radar. Ferrite is a ceramic composite oxide with ferromagnetic properties. It causes Faraday rotation and other nonreciprocal properties when interacting with microwaves. Therefore, it has been widely used in phased array radar. In this paper, the structure, electronic properties, chemical bonds and polarization properties of ABi₂Nb₂O₉ (A=Ba, Pb, Sr, Ca) system were analyzed based on the ferroelectric material, which is the basic material of the ferrite phase shifter. According to the results of the analysis, this system has similar ferroelectric origins. Some structures within the hybrid system for the distortion and the stability of the ferroelectric phase plays an important role. The stability of the ferroelectric phase stabilizes the phase shifter plays a key role. Moreover, this paper presents the changes of the distortion parameters based on different A-site ions, and verifies the correctness of the theoretical calculation by making a comparison with the experimental results.