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arXiv · 1212.1489

Neutron scattering study of correlated phase behavior in Sr2IrO4

Chetan Dhital·Tom Hogan·Z. Yamani·Clarina de la Cruz·Xiang Chen·Sovit Khadka·Zhensong Ren·Stephen D. Wilson
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Abstract

Neutron diffraction measurements are presented exploring the magnetic and structural phase behaviors of the candidate J$_{eff}=1/2$ Mott insulating iridate Sr$_2$IrO$_4$. Comparisons are drawn between the correlated magnetism in this single layer system and its bilayer analog Sr$_3$Ir$_2$O$_7$ where both materials exhibit magnetic domains originating from crystallographic twinning and comparable moment sizes. Weakly temperature dependent superlattice peaks violating the reported tetragonal space group of Sr$_2$IrO$_4$ are observed supporting the notion of a lower structural symmetry arising from a high temperature lattice distortion, and we use this to argue that moments orient along a unique in-plane axis demonstrating an orthorhombic symmetry in the resulting spin structure. Our results demonstrate that the correlated spin order and structural phase behaviors in both single and bilayer Sr$_{n+1}$Ir$_{n}$O$_{3n+1}$ systems are remarkably similar and suggest comparable correlation strengths in each system.

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Chetan Dhital, Tom Hogan, Z. Yamani, Clarina de la Cruz, Xiang Chen, Sovit Khadka, Zhensong Ren, Stephen D. Wilson. 2013-04-08. Neutron scattering study of correlated phase behavior in Sr2IrO4. https://doi.org/10.1103/physrevb.87.144405

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