High frequency impedance spectra on the chromium dioxide thin film

We report on the study of high frequency magnetotransport properties of the chromium dioxide (CrO2) thin films, grown on Si substrate using chemical v apor deposition. The film exhibits a ferromagnetic transition with a Curie temperature near 390 K. The temperature dependent spontaneous magnetization follows Bloch's law. The impedance spectra, being analyzed based on the fu ndamental electrodynamics, are demonstrated to be in a low-loss dielectric limit along with the occurrence of dielectric relaxation and magnetization response. The specific features of impedance spectra, distinct from the usu al metallic ferromagnet, are attributed to the half metallic nature of CrO2 . The results explore the possibility for high frequency device application s.