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تسجيل مستخدم جديدMagnetic excitations in a new anisotropic Kagom{e} antiferromagnet
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Julien Robert
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The Nd-langasite compound contains planes of magnetic Nd3+ ions on a lattice topologically equivalent to a kagom{e} 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 kagom{e} antiferromagnet.
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