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Theoretical investigation of the magnetic structure in YBa_2Cu_3O_6

Ekkehard Krüger
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Abstract

As experimentally well established, YBa_2Cu_3O_6 is an antiferromagnet with the magnetic moments lying on the Cu sites. Starting from this experimental result and the assumption, that nearest-neighbor Cu atoms within a layer have exactly antiparallel magnetic moments, the orientation of the magnetic moments has been determined within a nonadiabatic extension of the Heisenberg model of magnetism, called nonadiabatic Heisenberg model. Within this group-theoretical model there exist four stable magnetic structures in YBa_2Cu_3O_6, two of them are obviously identical with the high- and low-temperature structure established experimentally. However, not all the magnetic moments which appear to be antiparallel in neutron-scattering experiments are exactly antiparallel within this group-theoretical model. Furthermore, within this model the magnetic moments are not exactly perpendicular to the orthorhombic c axis.

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Ekkehard Krüger. 2006-08-07. Theoretical investigation of the magnetic structure in YBa_2Cu_3O_6. https://doi.org/10.1103/physrevb.75.024408

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