Pressure Effects on NMR and PQR Properties of CeCu6 and CeCu2Si2

NMR and PQR techlques under high pressure are used to study the pressure effects of the nuclear relaxation and quadruple interaction in the Kondo lattice compounds down to 0.6K. The temperature independent T 1 of 63 Cu of the PQR spectra are reduced by pressure in their magnetic regime. The Korringa relation, which is expected in the Fermi liquid state, appears below 1K at 5.4kbar in CeCu 6 , indicating that the coherency becomes stable at higher temperature by pressure. The quadruple interactions at each Cu site increase differently with pressure in CeCu 6 , reflecting the anisotropic compressibility for each axis.