Eur. Phys. J. B 11, 401-406 (1999)
https://doi.org/10.1007/s100510050950

Weak ferromagnetism in LaMnO₃

¹ Physics Department, Trinity College, Dublin 2, Ireland
² Institut d'Électronique Fondamentale, Université Paris-Sud, 91405 Orsay Cedex, France
³ Laboratoire de Chimie des Solides, Université Paris-Sud, 91405 Orsay Cedex, France

Corresponding author: ^a fott@spec.saclay.cea.fr

Received: 8 January 1999
Published online: 15 October 1999

Abstract

The magnetic properties of crystals have been studied. The ac susceptibility has been measured at frequencies ranging from 10 Hz to 1 000 Hz. The x = 0.25 crystal shows a typical ferromagnetic behaviour with a dimensionless SI susceptibility of 6 below limited by the demagnetizing field. Both x = 0 and x = 0.06 crystals show very sharp peaks in and at the Néel points, 139 K and 135 K respectively. This is quite unlike the usual behaviour of an antiferromagnet. Magnetization measurements on an untwinned single crystal of show a weak moment of at 4.2 K which is directed along the c axis. The origin of this canted antiferromagnetic structure is discussed in terms of anisotropy and of Dzyaloshinskii-Moriya interaction. It is concluded that anistropy is insufficient to explain the canted antiferromagnetism.