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arXiv · 0710.3025

Formation of collective spins in frustrated clusters

Julien Robert·Virginie Simonet·Benjamin Canals·Rafik Ballou·Elsa Lhotel·Céline Darie·Pierre Bordet·Bachir Ouladdiaf·Marc Johnson·Jacques Ollivier·Daniel Braithwaite·Harison Rakoto·Sophie De Brion
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Abstract

Using magnetization, specific heat and neutron scattering measurements, as well as exact calculations on realistic models, the magnetic properties of the \lacuvo compound are characterized on a wide temperature range. At high temperature, this oxide is well described by strongly correlated atomic $S$=1/2 spins while decreasing the temperature it switches to a set of weakly interacting and randomly distributed entangled pseudo spins $\tilde S=1/2$ and $\tilde S=0$. These pseudo-spins are built over frustrated clusters, similar to the kagomé building block, at the vertices of a triangular superlattice, the geometrical frustration intervening then at different scales.

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Julien Robert, Virginie Simonet, Benjamin Canals, Rafik Ballou, Elsa Lhotel, Céline Darie, Pierre Bordet, Bachir Ouladdiaf, Marc Johnson, Jacques Ollivier, Daniel Braithwaite, Harison Rakoto, Sophie De Brion. 2008-08-13. Formation of collective spins in frustrated clusters. https://doi.org/10.1103/physrevb.77.054421

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