Superconductor And ESR Properties Of 3D-metal Doped CeFeAsO

Many group in the world do lots of study in Fe-based superconductor since it was discovered. Many important progresses has been made in experiment and theory fields. People hope to discover more higher superconductor temperature Tc and also hope to have a clear image of superconductivity.In chapter 1, we briefly review the fundamental properties and the research history of superconductors, and make a brief introduction to the superconductor mechanism and structure. In the end, we show the latest progress in superconductor materials and theory.In chapter 2, we mainly introduce the doped-effect in Fe-based superconductor. We summarize the biggest Tc in FeAs-1111, FeAs-122, FeAs-111 and FeAs-11 system. Doped effects in FeAs surface and out of FeAs surface also have been introduced. Our work are also involved.In chapter 3, we introduced three important techniques of preparing Fe-based superconductors. We synthesize 3d metal-doped CeFeAsO samples. The theories of XRD technique, resistivity, SEM and ESR measurement have been shown.In chapter 4, we mainly introduce the properties with many techniques. The results of XRD experiment, SEM and resistivity prove that our sample quality is very good. The emphasis is that we introduce the meaning of parameters of ESR. We think that Co-doped CeFeAsO contains ferromagnetic clusters and this system is strongly correlated system.