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arXiv · 1408.6576

Short-range magnetic correlations in the highly-correlated electron compound CeCu$_{4}Ga

B. G. Ueland·C. F. Miclea·K. Gofryk·Y. Qiu·F. Ronning·R. Movshovich·E. D. Bauer·J. S. Gardner·J. D. Thompson
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Abstract

We present experimental results for the heavy-electron compound CeCu$_{4}$Ga which show that it possesses short-range magnetic correlations down to a temperature of $T = 0.1$ K. Our neutron scattering data show no evidence of long-range magnetic order occurring despite a peak in the specific heat at $T^{*} =1.2$ K. Rather, magnetic diffuse scattering occurs which corresponds to short-range magnetic correlations occurring across two unit cells. The specific heat remains large as $T\sim0$ K resulting in a Sommerfeld coefficient of $\gamma_{0} = 1.44(2)$ J/mol-K$^{2}$, and, below $T^{*}$, the resistivity follows $T^{2}$ behavior and the ac magnetic susceptibility becomes temperature independent. A magnetic peak centered at an energy transfer of $E_{\rm{c}}=0.24(1)$ meV is seen in inelastic neutron scattering data which shifts to higher energies and broadens under a magnetic field. We discuss the coexistence of large specific heat, magnetic fluctuations, and short-range magnetic correlations at low temperatures and compare our results to those for materials possessing spin-liquid behavior.

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B. G. Ueland, C. F. Miclea, K. Gofryk, Y. Qiu, F. Ronning, R. Movshovich, E. D. Bauer, J. S. Gardner, J. D. Thompson. 2014-08-27. Short-range magnetic correlations in the highly-correlated electron compound CeCu$_{4}Ga. https://doi.org/10.1103/physrevb.90.121109

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