Point-Contact Spectroscopy on Sr 2 RuO 4

We report on point-contact spectroscopy experiments on superconducting Sr 2 RuO 4 . For current injection into the ab-plane two distinctly different types of spectra are observed, one with a double-minimum structure and one with a zero-bias anomaly which gives evidence for unconventional pairing in this system. For current injection into the c-direction non-spectroscopic effects are dominant.