BiMnTeO 6 : A multiaxis Ising antiferromagnet

N. Matsubara (1, 2, 3) , S. Petit (2, 3) , C. Martin (1) , F. Fauth (4) , E. Suard (5) , S. Rols (5) , F. Damay (2, 3)

1 CRISMAT - Laboratoire de cristallographie et sciences des matériaux
2 NFMQ - LLB - Nouvelles frontières dans les matériaux quantiques
3 LLB - UMR 12 - Laboratoire Léon Brillouin
4 ALBA Synchrotron light source [Barcelone]
5 ILL - Institut Laue-Langevin

The crystal and magnetic properties of honeycomb BiMnTeO6 have been studied between 1.5 and 300 K using synchrotron x-rays and neutron-scattering experiments. Commensurate magnetic ordering is observed below TN=10K, and corresponds to a noncollinear spin arrangement, with spins tilted away from the anisotropy easy-axis set by the Jahn-Teller distortion of the MnO6 octahedra. Inelastic-scattering experiments show two main nearly localized magnetic excitations, which can be well described by an exchange Hamiltonian involving weak Mn-Mn magnetic interactions and a crystal-field Hamiltonian characterizing the strong easy-axis anisotropy associated with the dz2 orbital ordering of Mn3+. The crystal-field levels can be accurately calculated, taking into account a transverse molecular field imposed by the magnetic ordering of the neighboring atoms below TN. This makes BiMnTeO6 an interesting example of a multiaxis Ising system in a self-imposed transverse magnetic field.

Mots clés: Jahn-Teller effect; Spin dynamics; Noncollinear magnets; Inelastic neutron scattering

Domaines: Physique [physics]; Matière Condensée [cond-mat]

N. Matsubara, S. Petit, C. Martin, F. Fauth, E. Suard, et al.. BiMnTeO 6 : A multiaxis Ising antiferromagnet. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2019, 100 (22), pp.220406. ⟨10.1103/PhysRevB.100.220406⟩. ⟨hal-02438330⟩