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arXiv · 1405.5697

Color theorems, chiral domain topology and magnetic properties of FexTaS2

Yoichi Horibe·Junjie Yang·Yong-Heum Cho·Xuan Luo·Sung Baek Kim·Yoon Seok Oh·Fei-Ting Huang·Toshihiro Asada·Makoto Tanimura·Dalyoung Jeong·Sang-Wook Cheong
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Abstract

Common mathematical theory can have profound applications in understanding real materials. The intrinsic connection between aperiodic orders observed in the Fibonacci sequence, Penrose tiling, and quasicrystals is a well-known example. Another example is the self-similarity in fractals and dendrites. From transmission electron microscopy experiments, we found that FexTaS2 crystals with x=1/4 and 1/3 exhibit complicated antiphase and chiral domain structures related to ordering of intercalated Fe ions with 2a*2a and sqrt3a*sqrt3a superstructures, respectively. These complex domain patterns are found to be deeply related with the four color theorem, stating that four colors are sufficient to identify the countries on a planar map with proper coloring, and its variations for two-step proper coloring. Furthermore, the domain topology is closely relevant to their magnetic properties. Our discovery unveils the importance of understanding the global topology of domain configurations in functional materials.

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Yoichi Horibe, Junjie Yang, Yong-Heum Cho, Xuan Luo, Sung Baek Kim, Yoon Seok Oh, Fei-Ting Huang, Toshihiro Asada, Makoto Tanimura, Dalyoung Jeong, Sang-Wook Cheong. 2014-05-22. Color theorems, chiral domain topology and magnetic properties of FexTaS2. https://arxiv.org/abs/1405.5697

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