Regensburg 2022 – wissenschaftliches Programm

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

DS: Fachverband Dünne Schichten

DS 20: Poster

DS 20.40: Poster

Mittwoch, 7. September 2022, 16:00–18:00, P3

Magnetic Field-Dependent Thermal Conductivity in Manganite Thin Films — •Vitaly Bruchmann-Bamberg, Karen Stroh, Pia Henning, and Vasily Moshnyaga — I. Physik. Inst. Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen

In perovskite manganites strong electron-phonon and spin-phonon coupling give rise to intriguing magneto-electric phenomena like colossal magnetoresistance (CMR), i.e. reduction of electrical resistivity by several orders of magnitude in an applied magnetic field of few Tesla. Since thermal conductivity of a solid contains both lattice and electronic contributions, a question of its manipulation by an external magnetic field can be addressed in CMR manganites.

Here we present temperature- and magnetic-field-dependent measurements of thermal conductivity by means of 3ω-technique in (La_0.6Pr_0.4)_0.7Ca_0.3MnO₃/MgO(100) thin films with a CMR ratio of [R(0T)-R(5T)]/R(5T)≈10⁴%. The observed significant change of the thermal conductivity, κ, in magnetic field [κ(5T)- κ(0T)]/κ(0T) = 16% close to T_C≈ 200K is caused by the electronic contribution in agreement with the Wiedemann-Franz law.