THEORY OF MAGNETIC SHORT-RANGE ORDER FOR HIGH-T-C SUPERCONDUCTORS

A theory of magnetic short-range order for high-ir, cuprates is presen ted on the basis of the one-band t-t'-Hubbard model combining the four -field slave-boson functional integral technique with the Bethe cluste r method. The groundstate phase diagram evaluated self-consistently at the saddle-point and pair-approximation levels shows the experimental ly observed suppression of magnetic long-range order in the favour of a paraphase with antiferromagnetic short-range order. In this phase th e uniform static spin susceptibility consists of interrelated itineran t and local parts and increases upon doping up to the transition to th e Pauli paraphase. Using realistic values of the Hubbard interaction w e obtain the cusp position and the doping dependence of the zero-tempe rature susceptibility in reasonable agreement with experiments on La2- deltaSrdeltaCuO4.