DPG Phi
Verhandlungen
Verhandlungen
DPG

Regensburg 2013 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 59: Correlated Electrons: Quantum-Critical Phenomena - Experiments

TT 59.11: Talk

Thursday, March 14, 2013, 18:00–18:15, H6

NMR as a local probe for ferromagnetic correlation and quantum criticality in 3d systems: YFe2Al10 and Ta(Fe1−xVx)2 — •P. Khuntia1, M. Brando1, A. Strydom2, M. Aronson3, G. Kreiner1, F. Steglich1, and M. Baenitz11Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany — 2Physics Department, University of Johannesburg,South Africa — 3Brookhaven National Laboratory, New York 11973, USA

Probing the q-averaged dynamic susceptibility at low energies, the spin lattice relaxation rate by T, (1/T1T) (SLR) is ideal for the investigation of FM and AFM spin fluctuations. At the verge of magnetic order, unusual scaling laws in T and H dependent SLR could be associated with quantum criticality. In YFe2Al10, fluctuation of Fe moments leads to enhanced χ and C/T values yielding large Wilson ratio accompanied by 27(1/T1T)∼ χ reveal the dominant role of FM fluctuations in the spin excitation spectra [1].Ta(Fe1−xVx)2 undergoes an itinerant AFM order, but for nominal V doping, the magnetic properties are reminiscent of itinerant FM at the verge of a FM instability. The enhanced M(T→0) supported by C/T∼ -lnT behavior suggest the persistence of FM fluctuations.Additionally,the 51(1/T1T)∼ T−0.8 dependence in small fields indicates the co-existence of FM and AFM spin fluctuations.The Korringa product implies FM correlation between itinerant moments. Presented systems pose special interest since the bulk and microscopic data support low lying magnetic phase transitions and both are naturally located in the vicinity of FM QCP without any external tuning parameter.
[1] Phys. Rev. B (R), in press (2012)

100% | Mobile Layout | Deutsche Version | Contact/Imprint/Privacy
DPG-Physik > DPG-Verhandlungen > 2013 > Regensburg