Superconducting Transition in Electron-Doped 12CaO 7Al2O3
نویسندگان
چکیده
It was reported that a mixed light metal oxide compound, 12CaO 7Al2O3 (C12A7), which is known as a constituent of aluminous cement, became a superconductor at an ambient pressure by the exclusive replacement of extra-framework oxygen ions in subnanometer-sized crystallographic cages with electrons. Temperature dependences of resistivity, magnetic susceptibility, and magnetic field dependent resistivity of single-crystals and thin films revealed superconducting transition at temperature (Tc) of 0:4K and a critical magnetic field of 30mT. Tc varies 0.2–0.4K with the electron concentration. The interaction of the anionic electrons in the free space (cages) with the cationic framework may be responsible for the emergence of the superconducting state. [doi:10.2320/matertrans.MBW200717]
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