Quantum Critical Fluctuations in the Heavy fermion compound Ce(Ni$_{0.935}$Pd$_{0.065}$)$_2$Ge$_2$

C. H. Wang; L. Poudel; A. E. Taylor; J. M. Lawrence; A. D. Christianson; S. Chang; J. A. Rodriguez-Rivera; J. W. Lynn; A. A. Podlesnyak; 1 G. Ehlers; R. E. Baumbach; E. D. Bauer; K. Gofryk; F. Ronning; K. J. McClellan; J. D. Thompson

doi:10.1088/0953-8984/27/1/015602

arXiv · 1411.3689

Quantum Critical Fluctuations in the Heavy fermion compound Ce(Ni$_{0.935}$Pd$_{0.065}$)$_2$Ge$_2$

C. H. Wang·L. Poudel·A. E. Taylor·J. M. Lawrence·A. D. Christianson·S. Chang·J. A. Rodriguez-Rivera·J. W. Lynn·A. A. Podlesnyak·1 G. Ehlers·R. E. Baumbach·E. D. Bauer·K. Gofryk·F. Ronning·K. J. McClellan·J. D. Thompson

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Abstract

Electric resistivity, specific heat, magnetic susceptibility, and inelastic neutron scattering experiments were performed on a single crystal of the heavy fermion compound Ce(Ni$_{0.935}$Pd$_{0.065}$)$_2$Ge$_2$ in order to study the spin fluctuations near an antiferromagnetic (AF) quantum critical point (QCP). The resistivity and the specific heat coefficient for $T \leq$ 1 K exhibit the power law behavior expected for a 3D itinerant AF QCP ($\rho(T) \sim T^{3/2}$ and $\gamma(T) \sim \gamma_0 - b T^{1/2}$). However, for 2 $\leq T \leq$ 10 K, the susceptibility and specific heat vary as $log T$ and the resistivity varies linearly with temperature. Furthermore, despite the fact that the resistivity and specific heat exhibit the non-Fermi liquid behavior expected at a QCP, the correlation length, correlation time, and staggered susceptibility of the spin fluctuations remain finite at low temperature. We suggest that these deviations from the divergent behavior expected for a QCP may result from alloy disorder.

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C. H. Wang, L. Poudel, A. E. Taylor, J. M. Lawrence, A. D. Christianson, S. Chang, J. A. Rodriguez-Rivera, J. W. Lynn, A. A. Podlesnyak, 1 G. Ehlers, R. E. Baumbach, E. D. Bauer, K. Gofryk, F. Ronning, K. J. McClellan, J. D. Thompson. 2014-11-13. Quantum Critical Fluctuations in the Heavy fermion compound Ce(Ni$_{0.935}$Pd$_{0.065}$)$_2$Ge$_2$. https://doi.org/10.1088/0953-8984/27/1/015602

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