MAGNETIC DYNAMICS IN LA2CUO4

A coherent account of the magnetic properties of La2CuO4 and other cuprates providing a quantitative understanding of the magnetic dynamics in both the ordered as well as disordered states, is presented within the framework of a generalized spin-wave theory applied in conjunction with scaling ideas. The unique qualitative features-the essentially linear falloff of the sublattice magnetization with temperature in the ordered state, the exponential temperature dependence of the spin correlation length in the disordered state, and the characteristic energy dependence of the integrated structure factor-result from the long-wavelength spin-wave dynamics in two dimensions.