Exchange bias in a single phase ferrimagnet

We report on peculiar magnetic hysteresis behavior of Ru0.25Cr0.75O2 thin films. We describe three unusual magnetic phenomena inherent to this material; (i) intrinsic positive exchange bias in a single phase epitaxial thin film ferrimagnet with the absence of a clear and distinct magnetic-magnetic interface, (ii) field modulation of the shifted M(H) loop along the field axis direction, and (iii) inverted hysteresis loops in which the overall area of the loop is nearly zero over the entire field cycle. These results can be understood within the context of a very unusual interface of the epitaxial film with the TiO2 (001) substrate.