Room Temperature Study of the Magnetic Moment of Ultra-Thin Fe on GaAs(100) and InAs(100)

Here we studied the two systems Fe/GaAs(100) and the closely related Fe/InAs(100)to determine the Fe magnetic moment as a function of thickness.Ultra-thin (0.4 -23 nm) Fe layers were epitaxially grown at RT in a UHV MBE chamber on GaAs(100) and InAs(100) substrates.The structural characterisation was performed ex-situ by high-resolution X-ray diffraction and reflectometry (XRR).Magnetic characterisation of the films was performed using vector magneto-optical Kerr effect (MOKE) measurements, polarized neutron reflectometry (PNR) and super-conducting quantum interference device (SQUID) measurements at RT.Although the reduction of the symmetry at the interface can lead to an enhancement of the total magnetic moment, this contribution seems recessive as compared to those arising from roughness or interdiffusion.