SPIN AND CHARGE STRUCTURE FACTOR OF THE 2-DIMENSIONAL HUBBARD-MODEL

The spin and charge structure factors are calculated for the Hubbard m odel on the square lattice near half filling using a spin-rotation inv ariant six-slave boson representation. The charge structure factor sho ws a broad maximum at the zone corner and is found to decrease monoton ically with increasing interaction strength and electron density and i ncreasing temperature. The spin structure factor develops with increas ing interaction two incommensurate peaks at the zone boundary and alon g the zone diagonal. Comparison with results of quantum Monte Carlo an d variational calculations is carried out and the agreement is found t o be good. The limitations of a random-phase-approximation type approa ch are pointed out. [S0163-1829(97)02829-4].