Dresden 2014 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 35: Correlated Electrons: Quantum-Critical Phenomena - Experiment I
TT 35.13: Vortrag
Dienstag, 1. April 2014, 12:45–13:00, HSZ 204
Fermi liquid breakdown and superconductivity in YFe2Ge2 — Yang Zou1, Zhuo Feng1,2, •Peter Logg1, Jiasheng Chen1, Giulio Lampronti3, and F. Malte Grosche1 — 1Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE — 2Dept. of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ — 3London Centre of Nanotechnology, University College London WC1H 0AH
The investigation of quantum critical phenomena associated with
incipient antiferromagnetic or spin density wave order in
transition metal compounds has been held back by the scarcity of
candidate systems in this class of materials. The paramagnetic
d-electron system YFe2Ge2 displays an unusually high
Sommerfeld ratio of the specific heat capacity C/T ≃
100 mJ/molK2 at low temperature and can be tuned to the
border of spin density wave order by partial substitution of Y with
isoelectronic Lu [1], suggesting that YFe2Ge2 is located close to
a spin density wave quantum critical point. Our ambient pressure,
low temperature measurements reveal signatures of Fermi liquid
breakdown such as an increasing C/T on cooling and a 3/2 power law
temperature dependence of the electrical resistivity. Moreover,
samples of YFe2Ge2 with high residual resistance ratios
display full superconducting transitions below Tc ≃
1.8 K in the electrical resistivity and up to 80%
Meissner volume fraction in bulk zero-field-cooled magnetisation measurements, or
20% in powdered samples [2].
S. Ran et al., Phil. Mag. 91, 4388 (2011).
Y. Zou et al., arXiv:1311.0247 (2013).