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arXiv · 1204.4375

Field-induced quantum fluctuations in the heavy fermion superconductor CeCu2Ge2

D. K. Singh·A. Thamizhavel·J. W. Lynn·S. Dhar·J. Rodriguez-Rivera·T. Herman
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Abstract

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 CeCu2Ge2, 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.

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D. K. Singh, A. Thamizhavel, J. W. Lynn, S. Dhar, J. Rodriguez-Rivera, T. Herman. 2012-04-19. Field-induced quantum fluctuations in the heavy fermion superconductor CeCu2Ge2. https://doi.org/10.1038/srep00117

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