Magnetically inhomogeneous ground state ofCeAl3: An NMR study

We report ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$ nuclear-magnetic-resonance (NMR) studies on partly oriented powder of ${\mathrm{CeAl}}_3$ in the temperature range between 0.03 and 10 K. Below 2 K the NMR line shape shows a broad structure, increasing in relative intensity with decreasing temperature. In part of the sample the nuclear magnetization relaxes via a single ${\mathit{T}}_1$, following a Korringa law below 0.6 K. The remaining fraction of nuclei relaxes via a distribution of lower relaxation rates. These two-component NMR spectra manifest a gradual and spatially inhomogeneous development of magnetic correlations in regions with strongly reduced Ce-ion moments.