Spin and orbital quantum numbers play a key role in the physics of Mott insulators, but in most systems they are connected only indirectly—via the Pauli exclusion principle and the Coulomb interaction. Iridium-based oxides (iridates) introduce strong spin–orbit coupling directly, such that these numbers become entwined together and the Mott physics attains a strong orbital character. In the layered honeycomb iridates this is thought to generate highly spin–anisotropic magnetic interactions, coupling the spin to a given spatial direction of exchange and leading to strongly frustrated magnetism. Here we report a new iridate structure that has the same local connectivity as the layered honeycomb and exhibits striking evidence for highly spin–anisotropic exchange. The basic structural units of this material suggest that a new family of three-dimensional structures could exist, the ‘harmonic honeycomb’ iridates, of which the present compound is the first example.
Modic KA, Smidt TE, Kimchi I, et al. Realization of a three-dimensional spin–anisotropic harmonic honeycomb iridate. Nature Communications. 2014;5. doi:10.1038/ncomms5203
Modic, K. A., Smidt, T. E., Kimchi, I., Breznay, N. P., Biffin, A., Choi, S., … Analytis, J. G. (2014). Realization of a three-dimensional spin–anisotropic harmonic honeycomb iridate. Nature Communications, 5. https://doi.org/10.1038/ncomms5203
Modic, Kimberly A, Tess E. Smidt, Itamar Kimchi, Nicholas P. Breznay, Alun Biffin, Sungkyun Choi, Roger D. Johnson, et al. “Realization of a Three-Dimensional Spin–Anisotropic Harmonic Honeycomb Iridate.” Nature Communications 5 (2014). https://doi.org/10.1038/ncomms5203.
K. A. Modic et al., “Realization of a three-dimensional spin–anisotropic harmonic honeycomb iridate,” Nature Communications, vol. 5, 2014.
Modic KA, Smidt TE, Kimchi I, Breznay NP, Biffin A, Choi S, Johnson RD, Coldea R, Watkins-Curry P, McCandless GT, Chan JY, Gandara F, Islam Z, Vishwanath A, Shekhter A, McDonald RD, Analytis JG. 2014. Realization of a three-dimensional spin–anisotropic harmonic honeycomb iridate. Nature Communications. 5.
Modic, Kimberly A., et al. “Realization of a Three-Dimensional Spin–Anisotropic Harmonic Honeycomb Iridate.” Nature Communications, vol. 5, 4203, Springer Science and Business Media LLC, 2014, doi:10.1038/ncomms5203.
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