Speaker
Description
The existence of an uncompensated magnetic order in epitaxial thin films of multiferroic bismuth ferrite (BiFeO3 or BFO) is still the subject of intense debate. The Time Differential Perturbed Angular Correlation (TDPAC) technique monitors local fields at the atomic scale without altering the structure of the investigated materials. Using such an approach, we observed that BFO epitaxial thin films exhibit local ferromagnetic order at the unit cell level. TDPAC data obtained at room temperature with the 111mCd probe show that the strong magnetic field (~ 5 Tesla) exists at the non-magnetic sublattice (Bi site). It is assumed that the nano-strain resulting from the mismatch between the substrate and the BFO thin film produces a non-zero net local magnetisation of the sample.
