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arXiv · 1210.8187

Quantum Tunneling in Half-Integer-Spin Kagome-Lattice Langasites

A. Zorko·F. Bert·P. Mendels·A. Potočnik·A. Amato·C. Baines·K. Marty·P. Bordet·P. Lejay·E. Lhotel·V. Simonet·R. Ballou
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Abstract

Employing the muon spin relaxation technique we evidence temperature independent magnetic fluctuations persisting down to the lowest temperatures in the samarium-based ($J=5/2$) kagome-lattice Langasite. A detailed bulk-magnetization characterization and comparison to the neodymium-based ($J=9/2$) compound allow us to assign the persistent spin dynamics to a quantum tunneling process. This is facilitated by pairwise anisotropic magnetic interactions, leading to a universal scaling of the muon relaxation. Our study reveals a remarkable analogy between weakly interacting half-integer-spin rare-earth magnets and molecular nanomagnets.

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A. Zorko, F. Bert, P. Mendels, A. Potočnik, A. Amato, C. Baines, K. Marty, P. Bordet, P. Lejay, E. Lhotel, V. Simonet, R. Ballou. 2012-10-30. Quantum Tunneling in Half-Integer-Spin Kagome-Lattice Langasites. https://arxiv.org/abs/1210.8187

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