Dielectric characterization of low-loss calcium strontium titanate fibers produced by laser floating zone technique for wireless communication

Abstract

Wireless communication technology assisted to a huge development during the last two decades, responding to the growing demand for small size and low weight devices such as cell phones and global positioning systems. The need for miniaturization and higher autonomy resulted in the development of new dielectric oxide ceramics with very specific properties, to be applied as dielectric resonators in filters, oscillators, and antennas. Some crucial properties as a high quality factor, high dielectric constant, and near zero temperature coefficient of resonant frequency must be considered during the selection of the appropriate materials. The present work deals with the preparation of calcium titanate (CaTiO3), strontium titanate (SrTiO3), and calcium strontium titanate (CaxSr1−xTiO3) fibers produced by laser floating zone (LFZ) technique. Our results show that fibers grown at lower pulling rates exhibit higher ϵ′, for all the studied frequency range, including the microwave region. Moreover, the quality factor is always high envisaging the possibility to include these materials in future wireless device applications.