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

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 $T^{\ast }=1.2$ K. Rather, magnetic diffuse scattering occurs which corresponds to short-range magnetic correlations occurring across two unit cells. The specific heat remains large as $T\sim 0$ K resulting in a Sommerfeld coefficient of ${\gamma }_0=1.44(2)$ J/mol-K${}^2$, and, below $T^{\ast }$, the resistivity follows $T^2$ behavior and the ac magnetic susceptibility becomes temperature independent. A magnetic peak centered at an energy transfer of $E_{\mathrm{c}}=0.24(1)$ 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.

5 pages, 3 figures, Eq. 1 typo corrected from previous version

References in corpus (1)

• Heavy Fermions and Quantum Phase Transitions