Determination of domain wall sidewise velocity: An electrical method

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Abstract
A method to attain the relation between the sidewise velocity and the field E, based only on electrical measurements, is described. It is based upon the hypothesis that switching current is proportional to the sum of all domain perimeters, and that this value must be a continuous function of time even when field E is not. The experimental method consists on observing the switching current disturbed by a small and short overvoltage applied in different instants of the domain switching.Measurements have been made on several samples of TGS varying overvoltage, application point, field, delay time td and temperature, thus obtaining that the value of ε defined as ε = d(In v)/d(In E) is noticeably independent of these changes if the applied field was small enough in order that nucleation processes were not significant during the switching, and if the beginning and the end of the switching were not taken into account. Therefore, under these conditions, the sidewise velocity of domain wall can be described by v = c · E2.