Abstract
The electron spin resonance in a NbAuPb Josephson junction is reported. The gold layer was alloyed with 100 to 1000 ppm Gd and
167Er, respectively. Resonances are observed in the
I–V cureves at frequencies equivalent to the crystal-field splitting of AuGd (1.0 and 1.7 GHz) and to the hyperfine splitting of Au
167Er (2.87 GHz). The basic idea of this type of ESR-Josephson spectroscopy and the application are discussed. The magnetic field dependence of
I
c is described and compared with a simulation.
