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arXiv · 2301.05282

Non-centrosymmetric Sr$_{2}$IrO$_{4}$ obtained under High Pressure

Haozhe Wang·Madalynn Marshall·Zhen Wang·Kemp W. Plumb·Martha Greenblatt·Yimei Zhu·David Walker·Weiwei Xie
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Abstract

Sr$_{2}$IrO$_{4}$ with strong spin-orbit coupling (SOC) and Hubbard repulsion (U) hosts Mott insulating states. The similar crystal structure, magnetic and electronic properties, particularly the $d$-wave gap observed in Sr$_{2}$IrO$_{4}$ enhanced the analogies to cuprate high-$T_{c}$ superconductor, La$_{2}$CuO$_{4}$. The incomplete analogy was due to the lack of broken inversion symmetry phases observed in Sr$_{2}$IrO$_{4}$. Here, under high pressure and high temperature conditions, we report a non-centrosymmetric Sr$_{2}$IrO$_{4}$. The crystal structure and its noncentrosymmetric character were determined by single crystal X-ray diffraction and high-resolution scanning transmission electron microscopy (HR-STEM). The magnetic characterization confirms the Ir$^{4+}$ with $S$ = 1/2 at low temperature in Sr$_{2}$IrO$_{4}$ with magnetic ordering occurred at around 86 K, where a larger moment is observed than the ambient pressure Sr$_{2}$IrO$_{4}$. Moreover, the resistivity measurement shows three-dimensional Mott variable-range hopping existed in the system. This non-centrosymmetric Sr$_{2}$IrO$_{4}$ phase appears to be a unique material to offer further understanding of high-$T_{c}$ superconductivity.

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Haozhe Wang, Madalynn Marshall, Zhen Wang, Kemp W. Plumb, Martha Greenblatt, Yimei Zhu, David Walker, Weiwei Xie. 2023-01-12. Non-centrosymmetric Sr$_{2}$IrO$_{4}$ obtained under High Pressure. https://doi.org/10.1021/acs.inorgchem.2c03835

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