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Field-induced quantum fluctuations in the heavy fermion superconductor CeCu(2)Ge(2).

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 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.

SUBMITTER: Singh DK

PROVIDER: S-EPMC3216598 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Field-induced quantum fluctuations in the heavy fermion superconductor CeCu(2)Ge(2).

Singh D K DK Thamizhavel A A Lynn J W JW Dhar S S Rodriguez-Rivera J J Herman T T

Scientific reports 20111013

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 antif ...[more]

PMID: 22355634

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