This paper describes the first 63-Cu NMR study of an electron-doped
infinitely-layered high Tc superconductor Sr0β.9La0β.1CuO2β (Tc=42K). The
spin dynamics in the normal state above Tc exhibits qualitatively the same
behavior as some hole-doped materials with significantly enhanced spin
fluctuations. Below Tc, we observed no signature of a Hebel-Slichter coherence
peak, suggesting an unconventional nature of the symmetry of the
superconducting order parameter.Comment: Invited Paper to SNS-95 Conference (Spectroscopies on Novel
Superconductors 1995 at Stanford). Also presented at Aspen Winter Conference
on Superconductivity and Grenoble M^2S-HTSC in 199