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arXiv · 1404.5818

Spiral order in the honeycomb iridate Li2IrO3

Johannes Reuther·Ronny Thomale·Stephan Rachel
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Abstract

The honeycomb iridates A2IrO3 (A=Na, Li) constitute promising candidate materials to realize the Heisenberg-Kitaev model (HKM) in nature, hosting unconventional magnetic as well as spin liquid phases. Recent experiments suggest, however, that Li2IrO3 exhibits a magnetically ordered state of incommensurate spiral type which has not been identified in the HKM. We show that these findings can be understood in the context of an extended Heisenberg-Kitaev scenario satisfying all tentative experimental evidence: (i) the maximum of the magnetic susceptibility is located inside the first Brillouin zone, (ii) the Curie-Weiss temperature is negative relating to dominant antiferromagnetic fluctuations, and (iii) significant second-neighbor spin-exchange is involved.

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Johannes Reuther, Ronny Thomale, Stephan Rachel. 2014-04-23. Spiral order in the honeycomb iridate Li2IrO3. https://doi.org/10.1103/physrevb.90.100405

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