Short-range magnetic correlations in the highly correlated electron compound CeCu4Ga

We present experimental results for the heavy-electron compound CeCu4Ga 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 similar to 0 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-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.

Correlations