Resistance noise in spin valves
  Fluctuations of the magnetization in spin valves are shown to cause resistance noise that strongly depends on the magnetic configuration. Due to the applied external field and the dynamic exchange interaction through the normal metal spacer, the electrical noise level of the antiparallel configuration can exceed that of the parallel one by an order of magnitude, in agreement with recent experimental results. 
Jorn Foros, Arne Brataas, Gerrit E. W. Bauer and Yaroslav Tserkovnyak