Magnetization reversal at elevated temperatures in Co/Pt multilayer thin films

In this paper we report upon a study of the magnetization reversal mechanis ms in Co/Pt thin films at elevated temperatures. An alternating gradient fo rce magnetometer has been modified in order to perform measurements at elev ated temperatures. The data obtained from hysteresis loops and remanence cu rves measured at high temperature has been used to analyse reversal mechani sms which are discussed in terms of a well established two-coercivity model . The high sensitivity of the magnetic measurements reveal subtle temperatu re dependent changes in the magnetic characteristics of the films, which ar e attributed to thermally induced modifications of the energy barriers to m agnetization reversal and film microstructure. The evolution of domain stru cture during reversal has been examined by magnetic force microscopy for a sample placed in varying remanent states at elevated temperatures and is fo und to correlate with the two-coercivity model. Additionally, a method by w hich samples may be demagnetized in situ at elevated temperatures is discus sed along with domain wall motion induced by the stray field from magnetic force microscope tips.