NIST Center for Neutron Research, Gaithersburg, MD 20899, USA.
Sci Rep. 2011;1:117. doi: 10.1038/srep00117. Epub 2011 Oct 13.
Quantum-mechanical fluctuations in strongly correlated electron systems cause unconventional phenomena such as non-Fermi liquid behavior, and arguably high temperature superconductivity. Here we report the discovery of a field-tuned quantum critical phenomenon in stoichiometric CeCu(2)Ge(2), a spin density wave ordered heavy fermion metal that exhibits unconventional superconductivity under ≃10 GPa of applied pressure. Our finding of the associated quantum critical spin fluctuations of the antiferromagnetic spin density wave order, dominating the local fluctuations due to single-site Kondo effect, provide new information about the underlying mechanism that can be important in understanding superconductivity in this novel compound.
强关联电子系统中的量子力学涨落导致了非费米液体行为等非常规现象，也可以说是高温超导现象。在这里，我们报告了在化学计量 CeCu(2)Ge(2)中发现的一个场调量子临界现象，CeCu(2)Ge(2)是一种自旋密度波有序的重费米子金属，在施加约 10 GPa 的压力下表现出非常规超导性。我们发现了与反铁磁自旋密度波有序相关的量子临界自旋涨落，这些涨落主导了由于单原子 Kondo 效应引起的局域涨落，这为理解这种新型化合物中的超导性提供了关于潜在机制的新信息。
