Neutron-scattering and resistivity experiments on single crystals of La1.95Ba0.05CuO4 are described. On warming to as high as 250 K, the correlation length does not change, and the temperature dependence of the generalized susceptibility (Q,) is due solely to the temperature-dependence of the local response. We show that the associated relaxation rate in the metallic regime is Latin small letter h with stroke1/2kBT, in accord with the marginal-Fermi-liquid hypothesis, and relate our results to nuclear spin-lattice relaxation data. © 1991 The American Physical Society.

We use inelastic neutron scattering to establish the modulation vectors and correlation lengths for the incommensurate magnetic fluctuations in metallic samples of La2-xSrxCuO4 with x=0.075 and 0.14. In notation appropriate for a square lattice where the magnetic instability in the undoped case occurs at (,), the vectors are along (,0) and (0,).The correlation length is larger than the distance between carriers, is weakly dependent on x, and changes significantly between 12 and 100 K for both compositions. © 1991 The American Physical Society.