Incommensurate magnetic fluctuations in La_2xSr_xCuO₄

We use inelastic neutron scattering to establish the modulation vectors-delta 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 (pi,pi), the vectors-delta are along (pi,0) and (0,pi).

The correlation length-zeta is larger than the distance between carriers, is weakly dependent on chi, and changes significantly between 12 and 100 K for both compositions.