Competing interactions and complex magnetism at SrRuO3/SrMnO3 interfaces

The coupled interfacial Mn and Ru spin configurations in a SrRuO(3)(SRO)/SrMnO(3)(SMO) superlattice are investigated with x-ray resonant techniques. With an out-of-plane applied field H, a net Mn moment is induced opposite to (along) H below (above) SRO Curie temperature T(C), due to changes in interfacial antiferromagnetic Ru-Mn coupling. In comparison with the Mn moment induced along an out-of-plane field below T(C), the Mn moment induced along an in-plane field is five (three) times smaller below (above) T(C), due to frustration in the Ru-Mn coupling. Despite its in-plane anisotropy, the G-type antiferromagnetic SMO favors out-of-plane over in-plane canting of Mn moments.