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Magnetic excitations in a new anisotropic Kagomé antiferromagnet

Julien Robert·Virginie Simonet·Benjamin Canals·Rafik Ballou·Pierre Bordet·Isabelle Gelard·Alain Ibanez·Pascal Lejay·Jacques Ollivier·Anne Stunault
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Abstract

The Nd-langasite compound contains planes of magnetic Nd3+ ions on a lattice topologically equivalent to a kagomé net. The magnetic susceptibility does not reveal any signature of long-range ordering down to 2 K but rather a correlated paramagnetism with significant antiferromagnetic interactions between the Nd and a single-ion anisotropy due to crystal field effect. Inelastic neutron scattering on Nd-langasite powder and single-crystal allowed to probe its very peculiar low temperature dynamical magnetic correlations. They present unusual dispersive features and are broadly localized in wave-vector Q revealing a structure factor associated to characteristics short range-correlations between the magnetic atoms. From comparison with theoretical calculations, these results are interpreted as a possible experimental observation of a spin liquid state in an anisotropic kagomé antiferromagnet.

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Julien Robert, Virginie Simonet, Benjamin Canals, Rafik Ballou, Pierre Bordet, Isabelle Gelard, Alain Ibanez, Pascal Lejay, Jacques Ollivier, Anne Stunault. 2006-05-10. Magnetic excitations in a new anisotropic Kagomé antiferromagnet. https://doi.org/10.1016/j.physb.2006.05.106

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