21 research outputs found
Fractional Equations of Curie-von Schweidler and Gauss Laws
The dielectric susceptibility of most materials follows a fractional
power-law frequency dependence that is called the "universal" response. We
prove that in the time domain this dependence gives differential equations with
derivatives and integrals of noninteger order. We obtain equations that
describe "universal" Curie-von Schweidler and Gauss laws for such dielectric
materials. These laws are presented by fractional differential equations such
that the electromagnetic fields in the materials demonstrate "universal"
fractional damping. The suggested fractional equations are common (universal)
to a wide class of materials, regardless of the type of physical structure,
chemical composition or of the nature of the polarization.Comment: 11 pages, LaTe
Dielectric Relaxation of La-Doped Zirconia Caused by Annealing Ambient
La-doped zirconia films, deposited by ALD at 300°C, were found to be amorphous with dielectric constants (k-values) up to 19. A tetragonal or cubic phase was induced by post-deposition annealing (PDA) at 900°C in both nitrogen and air. Higher k-values (~32) were measured following PDA in air, but not after PDA in nitrogen. However, a significant dielectric relaxation was observed in the air-annealed film, and this is attributed to the formation of nano-crystallites. The relaxation behavior was modeled using the Curie–von Schweidler (CS) and Havriliak–Negami (HN) relationships. The k-value of the as-deposited films clearly shows a mixed CS and HN dependence on frequency. The CS dependence vanished after annealing in air, while the HN dependence disappeared after annealing in nitrogen