Polarized neutron reflectometry on metal evaporated videotapes

An 11 mm wide recorder head was used to simulate the writing process on one- and two-layer Hi8 metal evaporated videotapes. Polarized neutron reflectometry was used to study the in-plane magnetization as a function of depth after the writing process. Data for different magnetic states were fitted simultaneously, with the same nuclear structure. Total in-plane magnetization from the fits agrees with VSM-results. The fitted models show that the recorder head writes throughout the whole depth in both tapes. The in-plane magnetization in the two-layer tape exhibits two maxima; it is oppositely directed in the two layers in remanence after perpendicular magnetization. These results show that polarized neutron reflectometry is a suitable technique to study the writing-mechanism on metal evaporated videotapes.