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arXiv · 1402.1008

Switching of Conducting Planes by Partial Dimer Formation in IrTe$_2$

Tatsuya Toriyama·Masao Kobori·Takehisa Konishi·Yukinori Ohta·Kunihisa Sugimoto·Jungeun Kim·Akihiko Fujiwara·Sunseng Pyon·Kazutaka Kudo·Minoru Nohara
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Abstract

Single-crystal X-ray diffraction was employed to study the structural-electronic phase transition of IrTe$_2$ at approximately 270 K. The low-temperature structure was found to be a triclinic (space group $P\bar{1}$) characterized by the partial formation of Ir$_2$ dimers in the triangular lattice of IrTe$_2$, resulting in a structural modulation with a wave vector of ${\bf q} = (1/5, 0, -1/5)$. First-principles band calculations demonstrate that tilted two-dimensional Fermi surfaces emerge in the triclinic phase, suggesting that switching of the conducting planes occurs from the basal plane of the trigonal IrTe$_2$ to the tilted plane normal to ${\bf q}$ of the triclinic IrTe$_2$.

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Tatsuya Toriyama, Masao Kobori, Takehisa Konishi, Yukinori Ohta, Kunihisa Sugimoto, Jungeun Kim, Akihiko Fujiwara, Sunseng Pyon, Kazutaka Kudo, Minoru Nohara. 2014-02-05. Switching of Conducting Planes by Partial Dimer Formation in IrTe$_2$. https://doi.org/10.7566/jpsj.83.033701

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