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non-Local Quantum Criticality in Ce(Ru_{1-x} Fe_x)_2 Ge_2 (x = x_c = 0.76)

W. Montfrooij·M. C. Aronson·B. D. Rainford·J. A. Mydosh·A. P. Murani·P. Haen·T. Fukuhara
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Abstract

We present the results of inelastic neutron scattering measurements, performed near the antiferromagnetic quantum critical point in Ce(Ru_{0.24} Fe_{0.76})_2 Ge_2. Both local and long range fluctuations of the local moments are observed, but due to the Kondo effect only the latter are critical. We propose a phenomenological expression which fits the energy $E$, temperature T and wave vector q dependences of the generalized susceptibility chi(q,E,T), describing the non-Fermi liquid E/T scaling found at every wave vector.

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W. Montfrooij, M. C. Aronson, B. D. Rainford, J. A. Mydosh, A. P. Murani, P. Haen, T. Fukuhara. 2002-07-18. non-Local Quantum Criticality in Ce(Ru_{1-x} Fe_x)_2 Ge_2 (x = x_c = 0.76). https://arxiv.org/abs/cond-mat/0207467

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