magnetized while other is non-magnetic
Materials can be magnetic or non-magnetic at particular temperatures, e.g., Fe is ferromagnetic below the Curie temperature, and paramagnetic above it. There are many different magnetic configurations, antiferromagnetic, ferrimagnetic and so on. You may consult some text book on that.
) and conventional parallel/anti-parallel magnetic configurations of GMR devices ?
That is just the same magnetic material (used for metal electrodes) with 2 different relative orientations (parallel / aniparallel) of magnetization vector in the 2 magnetic electrodes.
