Seminar ÚFKL: Michal Kiaba

Department of Condensed Matter Physics (ÚFKL) invites you to the lecture

Michal Kiaba:
Deposition, structural characterization and magnetic properties of perovskite heterostructures

We present two series of samples – La0.3Sr0.7CoO3 thin films and LaFeO3 / SrTiO3 superlattices, which were fabricated by pulsed laser deposition. La0.3Sr0.7CoO3 is a ferromagnetic perovskite, and we observed instability in the magnetic properties of the thin films due to the formation of oxygen vacancies. We investigated the use of LaAlO3 as a capping layer to preserve the oxygen content in the thin film. The second part of the talk is devoted to the deposition, structural analysis and magnetic properties of a superlattice composed of antiferromagnetic LaFeO3 and semiconducting SrTiO3. We used muon spin spectroscopy to investigate the magnetic properties of ultrathin LaFeO3 layers in the superlattice. We observed that LaFeO3 remains antiferromagnetic in a superlattice with 2 unit cells of LaFeO3 whereas it is suppressed in a superlattice with 1 unit of LaFeO3. The latter effect presumably occurs because of the enhanced spin fluctuations in the two-dimensional limit.