Regensburg 2010 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

TT: Fachverband Tiefe Temperaturen

TT 5: CE: Low-dimensional Systems - Materials 1

TT 5.4: Vortrag

Montag, 22. März 2010, 15:00–15:15, H18

Low temperature magnetic response of CePt surface alloy — •Annemarie Köhl, Christian Praetorius, Sebastian Brück, and Kai Fauth — Physikalisches Institut, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany

We have used X-ray magnetic circular dichroism (XMCD) at Cerium edges to determine the low temperature paramagnetic local moment response of a CePt intermetallic surface alloy. The ultrathin alloy film is prepared in situ by evaporation of few atomic layers of Ce onto Pt(111) and subsequent annealing. LEED patterns of the resulting alloy hint at a (1.85 × 1.85) superstructure. The temperature dependent susceptibility is partially compatible with the response of the crystal field split Ce 4f¹ state with a crystal field splitting of ≈ 60 K. Below 20 K our data are indicative of a magnetic phase transition at a critical temperature of ≈ 9 K. We discuss our results in view of the recent findings of Kondo lattice physics in the related CePt₅ surface alloy.