Berlin 2018 – wissenschaftliches Programm

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

TT: Fachverband Tiefe Temperaturen

TT 6: Quantum Magnets and Molecular Magnets (joint session TT/MA)

TT 6.13: Vortrag

Montag, 12. März 2018, 12:45–13:00, H 3010

Formation of Local Magnetic Order in Atomic-Scale Ir Junctions — •Markus Ritter, Martin Keller, Torsten Pietsch, and Elke Scheer — Department of Physics, University of Konstanz, D-78467 Konstanz, Germany

The transition metals Pt, Pd, and Ir are paramagnets close to the Stoner transition of ferromagnetism. However, in reduced dimensions, such as small clusters and atomic contacts, a magnetically ordered state has been predicted [1]. In atomic contacts of the elements Pt and Pd, the emergence of local magnetic order has been experimentally confirmed recently [2, 3]. Currently there is no demonstration of such phenomena in Ir. Therefore, we investigate the magnetic properties of atomic Ir contacts and monoatomic chains [4]. The occurrence of local magnetic order is deduced from magnetoconductance (MC) and anisotropic magnetoconductance (AMC) measurements. The rich MC behavior is interpreted in the framework of a microscopic model of the local magnetic configuration and is compared to earlier findings in Pt and Pd contacts. Furthermore, in many contacts electronic transport (d I /d V ) spectroscopy shows a pronounced zero-bias anomaly (ZBA) and further features, which are currently not fully understood. The ZBA is analyzed in the context of Kondo screening of the local magnetic moment in the junction.
Delin, Tosatti. Phys. Rev. B 68, 144434 (2003).
Strigl et al. Nat. Commun. 6, 6172 (2015).
Strigl et al. Phys. Rev. B 94, 144431 (2016).
Thiess et al. Phys. Rev. Lett. 103, 217201 (2009).