Eur. Phys. J. B 27, 459-466 (2002)
https://doi.org/10.1140/epjb/e2002-00178-9

Hole doping by Li substitution and antiferromagnetism in YBa₂Cu₃O_y studied by neutron powder diffraction measurements

¹ Laboratoire des Solides Irradiés, École Polytechnique, 91128 Palaiseau Cedex, France
² Laboratoire Léon Brillouin (CEA-CNRS), CEA/Saclay, 91191 Gif-sur-Yvette Cedex, France
³ Laboratoire de Physique du Solide, ESPCI, 10 rue Vauquelin, 75231 Paris Cedex 05, France

Corresponding author: ^a francoise.maury@polytechnique.fr

Received: 31 October 2001
Revised: 6 March 2002
Published online: 25 June 2002

Abstract

The magnetic structure of tetragonal insulating YBa₂CuLi_xO_y has been studied as a function of x and y. The Néel temperature and the mean ordered magnetic moment on the Cu2 sites were determined by neutron powder diffraction measurements. The decrease of these two parameters as compared to YBa₂Cu₃O₆ is much stronger for lithium than for zinc substitution. The difference is quantitatively explained by the presence of holes created in the CuO₂ planes. These holes arise from the substitution of plane Cu²⁺ by Li⁺. We suggest an explanation why such holes are not seen for the same substitution of plane Cu²⁺ by Li⁺ in orthorhombic superconducting YBa₂CuLi_xO.