Josephson Effect of Heavy-Fermion Superconductors Measured in a 3-Axes Magnetometer

Abstract

We have fabricated a 3-axes magnetometer that can reduce the residual magnetic field below 50 µG for each direction. Josephson critical current I c between a noncentrosymmetric superconductor (CePt 3 Si or LaPt 3 Si) and Al has been investigated inside it to avoid the magnetic-flux trapping during the superconducting transition and found to show a magnetic field H dependence similar to the previous one obtained using one-axis magnetometer; asymmetric patterns with respect to H = 0 are commonly observed for CePt 3 Si and LaPt 3 Si. This suggests that the residual-field components perpendicular to H applied for I c (H) measurements does not basically affect the I c (H) patterns.