Phase transformation during repeated thermomagnetic writing on MnBi(Sb) films

Abstract

Repeated thermomagnetic writing experiments on antimony doped MnBi films show a decrease of readout signals as a function of laser pulse duration with increasing number of thermal cycles. The loss of magnetooptical signal is an effect of a gradual phase transformation from the normal to the quenched high temperatures phase. An empirical formula allows to describe the correlation between the duration of the writing laser pulses, the number of thermal cycles, and the fraction of transformed phase. From the experimental behaviour a model conception of this transformation has been developed.