  The magnetic properties of trilayers consisting of a diluted magnetic alloy,
CuMn (Cu0.99Mn0.01), a soft ferromagnet, Py(Ni0.8Fe0.2), and an
antiferromagnet, alpha-Fe2O3, were investigated. The samples, grown by UHV
magnetron sputtering, were magnetically characterized in the temperature range
T = 3-100 K. Typical exchange bias features, namely clear hysteresis cycle
shifts and coercivity enhancements, were observed. Moreover the presence of an
inverse bias, which had been already reported for spin glass-based structures,
was also obtained in a well defined range of temperatures and CuMn thicknesses.
