Regensburg 2007 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 17: Heavy Fermions
TT 17.2: Vortrag
Mittwoch, 28. März 2007, 14:15–14:30, H18
Pressure depending µSR measurements on CeCu2Si2 — •Astrid Schneidewind1, Oliver Stockert2, Daniel Andreica3, Alex Amato3, Julia Arndt2, Hirale S. Jeevan2, Christoph Geibel2, and Frank Steglich2 — 1Institut für Festkörperphysik, TU Dresden, D-01062 Dresden, Germany — 2MPI-CPfS, Nöthnitzer Str. 40, D-01178 Dresden, Germany — 3Laboratory for Muon-Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
The heavy-fermion compound CeCu2Si2 is located quite close to a quantum phase transition (QPT) at the disappearence of magnetic order. Applying pressure the QTP can be tuned without any change of the amount of disorder. We performed weak transverse-field µSR measurements to investigate an A/S-type CeCu2Si2 single crystal and to study how the antiferromagnetic order vanishes under pressure and gives way to superconductivity. With increasing pressure the Néel temperature decreases until the magnetic signal finally vanished. In the superconducting state the magnetic volume decreases with lowering temperature while superconducting volume increases as expected from ambient pressure measurements [1]. This can be related to phase separation into magnetically ordered and superconducting regions. Surprisingly, the temperature range, where magnetism and superconductivity are co-existing, becomes narrower with increasing pressure. In conclusion, applying pressure leads to a stabilization of superconductivity and supression of antiferromagnetism in CeCu2Si2.
Stockert et al., Physica B374-375 (2006) 415.