Skip to content

Anisotropic superexchange of a 90 degree Cu-O-Cu bond

V. Yu. Yushankhai, R. Hayn

cond-mat.str-elarXiv:cond-mat/9902106

Abstract

The magnetic anisotropy af a rectangular Cu-O-Cu bond is investigated in second order of the spin-orbit interaction. Such a bond is characteristic for cuprates having edge sharing CuO2 chains, and exists also in the Cu3O4 plane or in ladder compounds. For a ferromagnetic coupling between the copper spins an easy axis is found perpendicular to the copper oxygen plaquettes in agreement with the experimental spin structure of Li2CuO2. In addition, a pseudo-dipolar interaction is derived. Its estimation in the case of the Cu3O4 plane (which is present for instance in Ba2Cu3O4Cl2 or Sr2Cu3O4Cl2) gives a value which is however two orders of magnitude smaller than the usual dipole-dipole interaction.

Create a lesson