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.
@article{arxiv.1204.4375,
title = {Field-induced quantum fluctuations in the heavy fermion superconductor CeCu2Ge2},
author = {D. K. Singh and A. Thamizhavel and J. W. Lynn and S. Dhar and J. Rodriguez-Rivera and T. Herman},
journal= {arXiv preprint arXiv:1204.4375},
year = {2012}
}