Cuprate Films
The high-Tc copper-oxide superconductors (cuprates) break the limit of superconducting transition temperature predicted by the BCS theory based on electron-phonon coupling, thus opens a new chapter in the superconductivity field. According to the valence of substitutes, the cuprates could be categorized into electron- and hole-doped types.
FeSe Films
FeSe-based superconductors have the simplest chemical composition and lattice structure in iron based superconductors,but have the most abundant physical properties. Its transition temperature can be tuned widely using various means, and it is an ideal object for studying iron based superconductivity. Our group can grow high quality FeSe thin films, and can tune the superconductivity and lattice structure of thin films by various means.
Spinel Oxide Films
The spinel oxide system has many novel intrinsic properties, which has attracted a lot of attention. At present, superconductivity has been found in two spinel oxides, LiTi2O4 and MgTi2O4.They both belong to the normal spinel structure with a general formula, AB2O4 (space group Fd-3m).A crystal cell of AB2O4 has 32 oxygen ions, forming 64 tetrahedra sites and 32 octahedra sites. Among them, 8 sites are occupied by A ions(8a equivalent positions), and 16 sites are occupied by B ions(16d equivalent positions ). Our group has prepared high quality LiTi2O4 superconducting films ,MgTi2O4 single-component superconducting films and [MgTi2O4/SrTiO3]2 superlattices.