  Exchange bias stems from the interaction between different magnetic phases
and therefore it generally occurs in magnetic multilayers. Here we present a
large exchange bias in a single SrRuO3 layer induced by helium ion irradiation.
When the fluence increases, the induced defects not only suppress the
magnetization and the Curie temperature, but also drive a metal-insulator
transition at a low temperature. In particular, a large exchange bias field up
to around 0.36 T can be created by the irradiation. This large exchange bias is
related to the coexistence of different magnetic and structural phases that are
introduced by embedded defects. Our work demonstrates that spintronic
properties in complex oxides can be created and enhanced by applying ion
irradiation.
