Emergence of exchange bias and giant coercive field enhancement by internal magnetic frustration in La0.67Sr0.33MnO3 thin films

We have studied the influence of controlled defects on magnetic properties La0.67Sr0.33MnO3 (LSMO) thin films. used 100 nm thick epitaxial LSMO films, which were grown SrTiO3 substrates and introduced stoichiometry changes using oxygen ion irradiation through nanoporous alumina masks. Oxygen mask creates cascades in spatially-modulated regions plane film. The samples compared before after irradiation. found that reduces ferromagnetic ordering temperature, decreases total magnetization, enhances coercivity, induces exchange bias below 50 K. coercivity enhancement is dramatically higher K can be associated with bias. These results explained by formation Mn-rich antiferromagnetic or ferrimagnetic phases within bombarded are coupled to non-irradiated - host.