DOPING DEPENDENCE OF ANTIFERROMAGNETISM IN COPPER OXIDES - AN ESTIMATION OF THE NEEL TEMPERATURE-BASED ON THE T-J MODEL

A mechanism of suppression of the antiferromagnetic long-range order i n slightly doped copper oxides is proposed. This suppression is due to a decay of spin waves into particle-hole pair excitations. A self-con sistent Born approximation is developed within the t - J model and irr educible Green's function method. It is shown that the Neel temperatur e drops sharply with increasing hole concentration in accordance with experiment.