Magnetic irreversibility of discontinuous Fe/CaF2 multilayers with thermal annealing

Abstract In this work, we discuss the magnetic properties of discontinuous Fe/CaF2 multilayers as-deposited at room temperature and after annealing in high vacuum at 350, 450 and 550°C for 1 h. Zero-field-cooled and field-cooled magnetization were measured as a function of the magnetic field and temperature. Strong magnetic irreversibility can be explained by spatial distribution of antiferromagnetic aggregates consisting of crystalline forms of FeF3 with the Neel temperature around 140 K.