LOW-TEMPERATURE ORDER IN THE HEAVY-FERMION COMPOUND CECU6

We have used nuclear-quadrupole-resonance (NQR) techniques to study Cu nuclei in two single-crystal samples of CeCu6 between 200 mu K and 20 mK. We present measurements of the NQR intensities and spin-lattice r elaxation times, T-1, at frequencies corresponding to three different sites in the crystal. Below 5 mK we observe deviations from standard m etallic behavior in both signal intensity and spin-lattice relaxation times. These deviations are unusual in that they are site dependent; t hey reveal the presence of one or more types of order in this system.