Ferromagnetic bubble clusters in Y$_{0.67}$Ca$_{0.33}$MnO$_3$ thin films

摘要

We studied the ferromagnetic topology in a Y$_{0.67}$Ca$_{0.33}$MnO$_3$ thinfilm with a combination of magnetic force microscopy and magnetizationmeasurements. Our results show that the spin-glass like behavior, reportedpreviously for this system, could be attributed to frustrated interfaces of theferromagnetic clusters embedded in a non-ferromagnetic matrix. We foundtemperature dependent changes of the magnetic topology at low temperatures,which suggests a non-static Mn$^{3+}$/Mn$^{4+}$ ratio.