Influence of coating permeability in thin-film pulse recording

A modified model of curves which uses a more realistic family of minor loops has been designed for a theory of pulse recording. The loops are defined by the initial and maximal permeability, and , as well as by the reversible permeability of the tape. The calculation of the demagnetizing field, the magnetization transition, and the effective flux through the reproduce head is carried out by solving the Poisson differential equation, taking into account the boundary conditions of a two-dimensional head model. The calculation is carried out for an isolated linear magnetization transition of nonzero width. It results in Fourier integrals, the solution being provided by series expansion or approximation. The pulse amplitude and pulsewidth are given as simplified analytical functions of the tape permeability.