High-frequency electrical transport in nitrogen incorporated nano-crystalline diamond films in the GHz regime

Abstract

Measurement of alternating current conductance in the gigahertz regime of free standing nitrogen incorporated nano-diamond films is reported. Using a simple and newly developed technique, the scattering parameters of the nanodiamond films were measured on coplanar waveguides. The conductance is evident as a crossover from insulating behaviour where G ∝ ω 2 to the metallic regime where G ∝ ω 0.9 . From the micro-Raman studies of the films we conclude that this crossover is due to the changes in the grain boundary morphology which is driven by the level of nitrogen during synthesis. These results are in agreement with previous direct current measurements.

Compositional dependence of magnetic and high frequency properties of nanogranular CoFe-Yttrium-doped Zirconia films

“…Qiu et al [12] adjusted the intensity and frequency of RF transmission signal attenuation by changing the geometric dimension of the dielectric layer. According to previous works, microwave properties can be significantly affected by the magnetic anisotropy (H k ) [13,14], and saturation magnetization (M s ), static permeability m s ¼ 1 þ 4pM s /H k , and resonance frequency f r ¼ c/ 2p(4pM s H k ) 1/2 , where c is the gyromagnetic factor.…”