Rapid suppression of exchange bias across thin Au spacer layers

Using a CoO/Au/Co trilayer system, the exchange bias across nonmagnetic spacers has been investigated. X-ray diffraction, Auger electron spectroscopy, and transmission electron microscopy have been applied to provide a detailed analysis of the layered structure. Investigations on the magnetic behavior reveal that relatively strong exchange coupling is maintained up to a nominal spacer layer thickness of 22.5 Angstrom. In contrast to recent studies on similar trilayers, the decrease of the exchange bias field with increasing spacer thickness is more abrupt and not a gradual exponential reduction.