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arXiv · 1707.03140

Putative spin liquid in the triangle-based iridate Ba$_3$IrTi$_2$O$_9$

W. -J. Lee·S. -H. Do·Sungwon Yoon·S. Lee·Y. S. Choi·D. J. Jang·M. Brando·M. Lee·E. S. Choi·S. Ji·Z. H. Jang·B. J. Suh·K. -Y. Choi
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Abstract

We report on thermodynamic, magnetization, and muon spin relaxation measurements of the strong spin-orbit coupled iridate Ba$_3$IrTi$_2$O$_9$, which constitutes a new frustration motif made up a mixture of edge- and corner-sharing triangles. In spite of strong antiferromagnetic exchange interaction of the order of 100~K, we find no hint for long-range magnetic order down to 23 mK. The magnetic specific heat data unveil the $T$-linear and -squared dependences at low temperatures below 1~K. At the respective temperatures, the zero-field muon spin relaxation features a persistent spin dynamics, indicative of unconventional low-energy excitations. A comparison to the $4d$ isostructural compound Ba$_3$RuTi$_2$O$_9$ suggests that a concerted interplay of compass-like magnetic interactions and frustrated geometry promotes a dynamically fluctuating state in a triangle-based iridate.

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W. -J. Lee, S. -H. Do, Sungwon Yoon, S. Lee, Y. S. Choi, D. J. Jang, M. Brando, M. Lee, E. S. Choi, S. Ji, Z. H. Jang, B. J. Suh, K. -Y. Choi. 2017-07-11. Putative spin liquid in the triangle-based iridate Ba$_3$IrTi$_2$O$_9$. https://doi.org/10.1103/physrevb.96.014432

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