EFFECT OF ENHANCED CURRENT CROWDING IN A CPW WITH A THIN FERROELECTRIC FILM

Enhanced current crowding is predicted at the edges of the conducting strips in thin ferroelectric film coplanar waveguides (CPWs). A minimu m current crowding depth is expected, which depends on the CPW geometr y and dielectric constant of the ferroelectric film. In practical CPW devices the enhanced current crowding can increase the conductor losse s by up to four times. The current crowding depth may be smaller than the skin depth or London penetration depth (for high temperature super conducting CPW).