Vortex lattice melting of the electron superconductor Nd1.85Ce0.15CuO4-δ

Superconducting transition onset around 30-31 K was reported for the repeated-vacuum/Ar-annealed and liquid-nitrogen-quenched sample of the high T c electron superconductor Nd 1.85 Ce 0.15 CuO 4-δ (δ = 0.07(2)). Vortex lattice melting near T c was observed for this oxygen-reduced superconductor. Low field ( * (T) which was found to vary as (1-T/T c ) 5/3 .