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Abstracts
O1.10
Superconductivity and Quantum Critical Behavior in the
antiferromagnetically ordered Heavy Fermion Compound Ce
3
PtIn
11
J. Prokleˇska(1), M. Kratochv´ılov´a(1), K. Uhl´ıˇrov´a(1), V. Sechovsk´y(1), J.
Custers(1)
1) Faculty of Mathematics and Physics, Charles University, DCMP, Ke Karlovu
5, 121 16 Praha 2, Czech Republic
Dimensionality plays a crucial role in the character of a magnetic quantum
critical point (QCP). In order to understand how the physics is influenced when
going from 3D to 2D Kondo structures the Ce
n
T
m
In
3
n
+2
m
(T = transition
metal, n=1, 2,..; m = 0, 1,..) family offers an alternative to otherwise artificially
grown lattices, with cubic CeIn
3
at the 3D and CeCoIn
5
as an example of the
opposite (2D) end of the series.
Here we discuss results on single crystals of Ce
3
PtIn
11
located in between.
At ambient pressure the compound undergoes two successive antiferromagnetic
(AFM) transitions at
T
1
= 2
.
17
K
and
T
N
= 2
K
. Superconductivity emerges in
the complex AFM state below
T
c
=0.32K. Both phenomena coexist in a wide
range of the pressure – temperature phase diagrams. The critical pressure to
reach the QCP (
T
N
= 0) equals
p
c
1
.
3
GPa
.
O1.11
Nuclear spin driven dynamics in non-equilibrium disordered quantum
systems
Annina Luck, Andreas Reiser, Andreas Fleischmann, Christian Enss
Kirchhoff Institute
for
Physics,
Heidelberg
University,
INF 227, D-69120 Heidelberg, Germany
The investigation of non-equilibrium disordered quantum systems with novel
experimental techniques have resulted in fundamentally new insights of their
dynamics. In particular, the importance of nuclear spins as surprisingly active
degrees of freedom at ultra-low temperatures has been revealed in recent
measurements on amorphous solids. These new findings are of high relevance to
many quantum devices, like quantum dots, qubits, SQUIDs, nano-mechanical
systems and quantum limited amplifiers. We present the experimental evidence for
a nuclear spin driven dynamics in non-equilibrium disordered quantum systems
and discuss a possible theoretical framework for such a mechanism.
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