Synthesis of K3C60 single crystal thin films with high critical currents

High quality K3C60 single crystal thin films have been synthesized on (001) mica substrates. The normal state electrical resistivity shows classic metallic temperature dependence and can be fit to a functional form of ρ{variant}(T)=a+bT2. The film has a sharp transition to superconductivity near 22K, with a 10% to 90% width less than 700 mK. The experimental data near Tc have poor agreements with the Aslmozov-Larkin type fluctuation. Furthermore, critical current density up to 50 000 A/cm2 has been obtained at 4.7 K by continuous DC measurements, the preliminary analysis indicate that Jc is proportional to 1-(T/Tc)3. © 1993.