J. Phys. I France
Volume 4, Numéro 3, March 1994
Page(s) 423 - 439
DOI: 10.1051/jp1:1994149
J. Phys. I France 4 (1994) 423-439

Stability of the atomic magnetic moments in La 2-xSr xCuO 4 and effect of their fluctuations on the electronic density of states

T. Hocquet1, J.-P. Jardin2, P. Germain1 and J. Labbé1

1  Laboratoire de Physique de la Matière Condensée de l'Ecole Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 05, France
2  Laboratoire PMTM (CNRS), Université Paris Nord, 93430 Villetaneuse, France

(Received 10 September 1993, accepted 29 November 1993)

We calculate the band structure of the antiferromagnetic phase of La 2-xSr xCuO 4 in a bidimensional itinerant electron model. Then, we discuss the stability of the antiferromagnetic phase and we calculate the size of the atomic magnetic moments with respect to the temperature and the doping ratio x. We show that the antiferromagnetic solution is in any case much more stable than the ferromagnetic one. Finally, we give a description of the antiferromagnetic fluctuations from which merges an explicit physical meaning of the pseudo-gap found in the electronic density of states. Implications for superconductivity are proposed.

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