Magnetic frustration in an iron based Cairo pentagonal lattice

Eric Ressouche (1) , Virginie Simonet (2) , Benjamin Canals (3) , Marin Gospodinov (4) , Vassil Skumryev (5, 6)

1 SPSMS - UMR 9001 - Service de Physique Statistique, Magnétisme et Supraconductivité
2 NEEL - MagSup - Magnétisme et Supraconductivité
3 NEEL - TMC - Théorie de la Matière Condensée
4 ISSP - Institut of the Solid State Physics
5 ICREA - Institució Catalana de Recerca i Estudis Avançats = Catalan Institution for Research and Advanced Studies
6 Department de Fisica

The Fe3+ lattice in the Bi2Fe4O9 compound is found to materialize the first analogue of a magnetic pentagonal lattice. Due to its odd number of bonds per elemental brick, this lattice, subject to first neighbor antiferromagnetic interactions, is prone to geometric frustration. The Bi2Fe4O9 magnetic properties have been investigated by macroscopic magnetic measurements and neutron diffraction. The observed non-collinear magnetic arrangement is related to the one stabilized on a perfect tiling as obtained from a mean field analysis with direct space magnetic configurations calculations. The peculiarity of this structure arises from the complex connectivity of the pentagonal lattice, a novel feature compared to the well-known case of triangle-based lattices.

Domaines: Electrons fortement corrélés [cond-mat.str-el]

Eric Ressouche, Virginie Simonet, Benjamin Canals, Marin Gospodinov, Vassil Skumryev. Magnetic frustration in an iron based Cairo pentagonal lattice. Physical Review Letters, 2009, 103, pp.267204. ⟨10.1103/PhysRevLett.103.267204⟩. ⟨hal-00443990⟩