Novel Charge Ordering in the Trimer Iridium Oxide BaIrO3

Ichiro Terasaki; Shun Ito; Taichi Igarashi; Shinichiro Asai; Hiroki Taniguchi; Ryuji Okazaki; Yukio Yasui; Kensuke Kobayashi; Reiji Kumai; Hironori Nakao; Youichi Murakami

arXiv · 1603.03525

Novel Charge Ordering in the Trimer Iridium Oxide BaIrO3

Ichiro Terasaki·Shun Ito·Taichi Igarashi·Shinichiro Asai·Hiroki Taniguchi·Ryuji Okazaki·Yukio Yasui·Kensuke Kobayashi·Reiji Kumai·Hironori Nakao·Youichi Murakami

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Abstract

We have prepared polycrystalline samples of the trimer Ir oxide BaIrO3 with face-shared Ir3O12 trimers, and have investigated the origin of the phase transition at 182 K by measuring resistivity, thermopower, magnetization and synchrotron x-ray diffraction. We propose a possible electronic model and transition mechanism, starting from a localized electron picture on the basis of the Rietveld refinement. Within this model, BaIrO3 can be basically regarded as a Mott insulator, when the Ir3O12 trimer is identified to one pseudo-atom or one lattice site. The transition can be viewed as a transition from the Mott insulator phase to a kind of charge ordered insulator phase.

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Ichiro Terasaki, Shun Ito, Taichi Igarashi, Shinichiro Asai, Hiroki Taniguchi, Ryuji Okazaki, Yukio Yasui, Kensuke Kobayashi, Reiji Kumai, Hironori Nakao, Youichi Murakami. 2016-03-11. Novel Charge Ordering in the Trimer Iridium Oxide BaIrO3. https://arxiv.org/abs/1603.03525

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