Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DF: Fachverband Dielektrische Festkörper

DF 22: Poster II

DF 22.11: Poster

Freitag, 15. März 2013, 10:30–13:30, Poster D

Growth of thin La_0.7Sr_0.3MnO₃ films on SrTiO₃ substrates with different orientations — •Danny Schwarzbach, Markus Jungbauer, Sebastian Hühn, Markus Michelmann, and Vasily Moshnyaga — I. Physikalisches Institut, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen

Thin film peculiarities like oxygen vacancies, epitaxial strain, orbital reconstruction at the interface and especially the polar catastrophe are of great interest for the physics and technology of correlated oxide films. We studied the growth and preparation of epitaxial films of La_0.7Sr_0.3MnO₃ with a thickness d=5−120 nm on SrTiO₃ substrates with (100), (110) and (111) orientations, to get more insight on the above effects.

All films were found to be coherently strained and show qualitatively similar ferromagnetic and metallic behaviour. However, the orientation of substrates influences significantly the values of Curie point T_C, metal-to-insulator transition temperature T_MI, coercive field H_C and magnetic anisotropy.

Especially the (111) films show the highest T_C and T_MI as well as the lowest H_C. For example, the film with d=30 nm reveals T_C=362 K and H_C(5 K) less than 2 - 5 Oe, which indicates practically the absence of magnetic anisotropy. The results are discussed within the orbital reconstruction and polar catastrophe, which both depend on the crystal orientations.

Support of EU Seventh Framework Programme via IFOX is acknowledged.