Thermosensitive Spin Valve Based on an Artificial Ferrimagnet: Magnetization Process in a Wide Range of Fields

Film structures of the Gd–Co/Co/Cu/Co type having the properties of heat-sensitive spin valves have been developed, fabricated, and investigated. The results of magnetic and magnetoresistive measurements in a wide range of fields and temperatures for these structures are presented. It is shown that the occurrence of noncollinear magnetic structure in the Gd–Co/Co system significantly affects the shape of the magnetoresistive hysteresis loops. The magnitude of the critical fields of magnetization reversal depends on the temperature and can vary due to a change in the ratio of thicknesses of the film system layers.