Kengo Okura

Preparation of Alkaline-Metal-Doped C60 Superconducting Film and Its Stabilization in Air with Protective Coatings

Preparation conditions of C60 film were studied by varying substrates, substrate temperature and the rate of evaporation. Crystalline C60 thin films were prepared on GaAs(100) at the substrate temperature of 100° C in order to obtain superconductors by alkaline metal doping. The Rb/Cs-doped film showed a superconducting transition with T c( onset)=24±3 K and T c( zero)=8 K. The composition of the superconducting film was measured by micro-Auger electron spectroscopy. Air stability of Rb3C60 superconducting film with protective coatings applied was studied. A Si protective film maintained superconductivity for 220 min in air. In addition a Si/Al protective coatings maintained superconductivity for 8 h.

Alkaline Metals Doping into C60 Thin Films

C60 thin films were prepared on GaAs(100) and quartz substrates by two different vapour deposition methods. Rb and Cs were found to be doped in crystalline C60 thin films by the resistance measurement during the course of the doping experiment. The Rb/Cs-doped film showed a superconducting transition at Tc(onset)=24±3 K and Tc(zero)=8 K. The composition of the superconducting film was investigated by µ-Auger Electron Spectroscopy (µ -AES). This is the first confirmation of superconductivity in a Cs/Rb-doped Cgo thin film.

Preparation of C60 Thin Films and Cs-Rb Doping

Abstract The effect of preparation conditions onto the crystallinity of C60 thin films were studied by using two different vapor deposition methods. Rb and Cs were found to be doped in C60 thin films by the resistance measurement during the course of the doping experiment. The Rb/Cs-doped film showed a superconducting transition at Tc(onset)=24±3K and Tc(zero)=8K.