Magnetic characterization of ultrathin EuO films with XMCD

We present work done on EuO films with thicknesses varying from 10 to 60 A grown as a stepped wedge on Si/SiO2/Cr(20 A)/Cu(90 A) and capped with Y(20 A)/Al(80 A). The films were characterized by x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) at the europium M5 and copper L3 edges. The films' high quality and consistent magnetic properties were confirmed by superconducting quantum interference device magnetometry, which revealed a constant saturation moment independent of film thickness. XAS at the Cu L3 edge showed that the bottom Cu electrode is metallic (oxidation free). We report an XMCD intensity of 52% (±4.3), in excellent agreement with theoretical calculations.