Thermal stability of tunneling spin polarization

We present a study of the thermal stabilityof tunneling spin polarization in Al/AlOx/ferromagnet junctions based on the spin-polarized tunneling technique, in which the Zeeman-split superconducting densityof states in the Al electrode is used as a detector for the spin polarization. Thermal robustness of the polarization, which is of keyimportance for the performance of magnetic tunnel junction devices, is demonstrated for post-deposition anneal temperatures up to 500 1C with Co and Co90Fe10 top electrodes, independent of the presence of an FeMn layer on top of the ferromagnet