title: Antiferromagnetic ordering in superconducting YBa2Cu3O6.5.
abstract: Commensurate antiferromagnetic ordering has been observed in the superconducting high- Tc cuprate YBa2Cu3O6.5 ( Tc = 55 K) by polarized and unpolarized elastic neutron scattering. The magnetic peak intensity exhibits a marked enhancement at Tc. Zero-field muon-spin-resonance experiments demonstrate that the staggered magnetization is not truly static but fluctuates on a nanosecond time scale. These results point towards an unusual spin density wave state coexisting with superconductivity.
authors.affiliation: Laboratoire Léon Brillouin, CEA-CNRS, CE Saclay, 91191 Gif sur Yvette, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Sidis
authors.forename: C
authors.initials: C
authors.lastname: Ulrich
authors.forename: P
authors.initials: P
authors.lastname: Bourges
authors.forename: C
authors.initials: C
authors.lastname: Bernhard
authors.forename: C
authors.initials: C
authors.lastname: Niedermayer
authors.forename: L P
authors.initials: LP
authors.lastname: Regnault
authors.forename: N H
authors.initials: NH
authors.lastname: Andersen
authors.forename: B
authors.initials: B
authors.lastname: Keimer