This basic patent for single heterogeneous alloy films which exhibit Giant Matgnetoresistance (GMR) was awarded on the basis of materials research performed under the MRSEC program at the University of California, San Diego.

These films can be used as rugged, cheap magnetic field sensors which can be very easily prepared by standard film techniques. Since they are eminently suitable for measuring rotational velocities, they are under intensive investigation by automobile companies for tachometer applications.

Another enormously important potential use for these films is to read out magnetically stored data written at ultra-high densities. These single films offer the promise of much higher output signals from data stored at high densities than do current devices which are generally much more complex. For this reason, there is great interest in these single GMR films among data storage companies. In fact, six of the largest US data storage companies have jointly co-licensed this patent.