according to fig1 however said value remains adequate it will be seen that the coil 18 is closer to the head gap than in the head according to fig1 which somewhat improves the writing field it is also possible to move the upper pole piece towards the plane of the coil the head of fig3 also comprises an element c which is a conductive layer into which can be injected a polarizing current in order to produce a polarization induction in the element mr the induction at rest i e in the absence of a reading field is then inclined with respect to the current lines used for reading the resistance variation of the element mr such an arrangement is known per se and is e g described in the case of a vertical head in u s pat no 4 734 644 however the presence of such a conductor is not obligatory preference compared therewith can be given to a so called barber pole conductive layer deposited on the actual element mr and creating an oblique current with respect to the longitudinal axis of the element mr a barber pole means is described in the article by m g j heijman et al entitled 34 multi track magnetic heads in thin film technology 34 published in 34 philips technical review 34 vol 44 no 6 december 1988 pp 169 178 the head of fig4 differs from that of fig3 by the addition of a lower pole piece 14 the writing field increases somewhat and rises to 2400 oe i e 192000 a m the lower pole piece has the effect of magnetically.