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arXiv · 1606.07691

Topological quantum phase transition driven by anisotropic spin-orbit coupling in trinuclear organometallic coordination crystals

J. Merino·A. C. Jacko·A. L. Khosla·B. J. Powell
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Abstract

We show how quasi-one-dimensional correlated insulating states arise at two-thirds filling in organometallic multinuclear coordination complexes described by layered decorated honeycomb lattices. The interplay of spin-orbit coupling and electronic correlations leads to pseudospin-1 moments arranged in weakly coupled chains with highly anisotropic exchange and a large trigonal splitting. This leads to a quantum phase transition from a Haldane phase to a topologically trivial phase as the relative strength of the spin-orbit coupling increases.

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J. Merino, A. C. Jacko, A. L. Khosla, B. J. Powell. 2016-06-24. Topological quantum phase transition driven by anisotropic spin-orbit coupling in trinuclear organometallic coordination crystals. https://doi.org/10.1103/physrevb.94.205109

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