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arXiv · 1505.00538

Honeycomb Charge Ordering in IrTe$_2$

Hyo Sung Kim·Soo-Ran Kim·Kyoo Kim·Byung Il Min·Yong-Heum Cho·Sang-Wook Cheong·Han Woong Yeom
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Abstract

We report on the observation of a unique honeycomb charge ordering of the cleaved IrTe$_2$ surface by high-resolution scanning tunneling microscopy (STM) and spectroscopy (STS). IrTe$_2$ was recently established to exhibit intriguing stripe charge orderings. Here, we show that the stripe charge order coexists with a metastable honeycomb phase formed locally. The atomic and electronic structures of the honeycomb phase are consistent with the stripe phase indicating unambiguously its charge order nature. A simple model of the honeycomb structure is suggested based on the overlap of three degenerate stripe orders, which is analogous to the 3$q$ state description of a skyrmion. We suggest that the honeycomb charge order can be a route to an exotic Dirac electron system.

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Hyo Sung Kim, Soo-Ran Kim, Kyoo Kim, Byung Il Min, Yong-Heum Cho, Sang-Wook Cheong, Han Woong Yeom. 2015-05-04. Honeycomb Charge Ordering in IrTe$_2$. https://arxiv.org/abs/1505.00538

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