DPG Phi
Verhandlungen
Verhandlungen
DPG

Regensburg 2010 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 16: CE: Quantum-Critical Phenomena 1

TT 16.1: Talk

Tuesday, March 23, 2010, 14:00–14:15, H19

Specific heat and magnetocaloric effect at the field-induced quantum-critical point in CeCu5.7Au0.3 — •Michael J. Wolf, Gernot Goll, Veronika Fritsch, and Hilbert v. Löhneysen — Karlsruher Institut für Technologie, 76131 Karlsruhe, Germany

The heavy-fermion system CeCu6−xAux can be tuned to a quantum critical point by application of different tuning parameters such as pressure or magnetic field. We present specific heat measurements on single crystalline CeCu5.7Au0.3 in the temperature range from 70 mK to 1.5 K and in magnetic fields up to 4 T with Bc. In addition, the magnetocaloric effect was measured in the temperature range from 70 mK to 1 K and in magnetic fields up to 2 T. The critical magnetic field Bc was determined to be Bc = 0.95±0.1 T. At the critical magnetic field the specific heat data can be well described by the self-consistent spin-fluctuation model of Moriya and Takimoto [1]. The magnetocaloric data at low temperatures show a jump of the magnetic Grüneisen ratio at the phase boundary for B < Bc as well as a monotonic increase towards the lowest measured temperatures for B > Bc. These results are compared to previous magnetization measurements and discussed within the framework of theoretical models.

[1] T. Moriya and T. Takimoto, J. Phys. Soc. Japan 64 (1995), 960.

100% | Mobile Layout | Deutsche Version | Contact/Imprint/Privacy
DPG-Physik > DPG-Verhandlungen > 2010 > Regensburg