Absolute determination of Co magnetic moments:: Ultrahigh-vacuum high-Tc SQUID magnetometry

A full-thickness dependent, from two monolayers to bulk, absolute determination of the total magnetic moments of Co/Cu(001) films is carried out ill situ with the help of UHV high-T-c SQUID magnetometer. The total moment is enhanced by 11% compared to the bulk value of 1.7 mu (B)/atom measured in the thick limit. These values agree perfectly with polarized neutron diffraction measurements for the bulk and confirm theoretical predictions for the ultrathin limit.