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arXiv · 1701.06117

Novel Magnetism and Local Symmetry Breaking in a Mott Insulator with Strong Spin Orbit Interactions

L. Lu·M. Song·W. Liu·A. P. Reyes·P. Kuhns·H. O. Lee·I. R. Fisher·V. F. Mitrović
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Abstract

Study of the combined effects of strong electronic correlations with spin-orbit coupling (SOC) represents a central issue in quantum materials research. Predicting emergent properties represents a huge theoretical problem since the presence of SOC implies that the spin is not a good quantum number. Existing theories propose the emergence of a multitude of exotic quantum phases, distinguishable by either local point symmetry breaking or local spin expectation values, even in materials with simple cubic crystal structure such as Ba$_2$NaOsO$_6$. Experimental tests of such theories by local probes are highly sought for. Here, we report on local measurements designed to concurrently probe spin and orbital/lattice degrees of freedom of Ba$_2$NaOsO$_6$. We find that a novel canted ferromagnetic phase which is preceded by local point symmetry breaking is stabilized at low temperatures, as predicted by quantum theories involving multipolar spin interactions.

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L. Lu, M. Song, W. Liu, A. P. Reyes, P. Kuhns, H. O. Lee, I. R. Fisher, V. F. Mitrović. 2017-01-22. Novel Magnetism and Local Symmetry Breaking in a Mott Insulator with Strong Spin Orbit Interactions. https://doi.org/10.1038/ncomms14407

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