With AC microwave measurements from 10 MHz up to 50 GHz and DC nanovolt level measurements we have investigated the superconducting phase transition of YBa2Cu3O7-delta films in zero magnetic field and electrical transport properties of single walled carbon nanotube networks.systematically depends on the applied microwave power, which may arise from a finite size effect. ... Because of these issues, we are forced to use a higher frequency range to obtain the critical exponents. At very high frequency, the calibration degrades and the process of removing the normal channel contribution makes Ifl vs. frequency show upward curvature. ... From the scaling theory log|I fl(f)| vs. log f is known to be a convex function below Tc and a concave function above Tc.

Title | : | Critical Behavior of Superconductors and Electrical Transport Properties of Carbon Nanotube Thin Films |

Author | : | Hua Xu |

Publisher | : | ProQuest - 2007 |

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