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Unusual Single-Ion Non-Fermi Liquid Behavior in Ce_(1-x)La_xNi_9Ge_4

U. Killer·E. -W. Scheidt·G. Eickerling·H. Michor·J. Sereni·Th. Pruschke·S. Kehrein
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Abstract

We report on specific heat, magnetic susceptibility and resistivity measurements on the compound Ce_(1-x)La_xNi_9Ge_4 for various concentrations ranging from the stoichiometric system with x=0 to the dilute limit x=0.95. Our data reveal single-ion scaling with the Ce-concentration and the largest ever recorded value of the electronic specific heat c/T approximately 5.5 J K^(-2)mol^(-1) at T=0.08K for the stoichiometric compound x=0 without any trace of magnetic order. While in the doped samples c/T increases logarithmically below 3K down to 50mK, their magnetic susceptibility behaves Fermi liquid like below 1K. These properties make the compound Ce_(1-x)La_xNi_9Ge_4 a unique system on the borderline between Fermi liquid and non-Fermi liquid physics.

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U. Killer, E. -W. Scheidt, G. Eickerling, H. Michor, J. Sereni, Th. Pruschke, S. Kehrein. 2004-09-13. Unusual Single-Ion Non-Fermi Liquid Behavior in Ce_(1-x)La_xNi_9Ge_4. https://doi.org/10.1103/physrevlett.93.216404

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