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arXiv · 1810.04913

Observation of Dirac-like energy band and unusual spectral line shape in quasi-one-dimensional superconductor Tl2Mo6Se6

Kosuke Nakayama·Zhiwei Wang·Chi Xuan Trang·Seigo Souma·Emile D. L. Rienks·Takashi Takahashi·Yoichi Ando·Takafumi Sato
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Abstract

We have performed high-resolution angle-resolved photoemission spectroscopy of the quasi-one-dimensional (1D) topological superconductor candidate Tl2Mo6Se6 consisting of weakly-coupled Mo3Se3 chains. We found a quasi-1D Fermi surface arising from a Dirac-like energy band, which is associated with the nonsymmorphic screw symmetry of the chains and predicted to trigger topological superconductivity. We observed a significant spectral-weight reduction over a wide energy range, together with a tiny Fermi-edge structure which exhibits a signature of a superconducting-gap opening below the superconducting-transition temperature. The observed quasi-1D Dirac-like band and its very small density of states point to an unconventional nature of superconductivity in Tl2Mo6Se6.

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Kosuke Nakayama, Zhiwei Wang, Chi Xuan Trang, Seigo Souma, Emile D. L. Rienks, Takashi Takahashi, Yoichi Ando, Takafumi Sato. 2018-10-11. Observation of Dirac-like energy band and unusual spectral line shape in quasi-one-dimensional superconductor Tl2Mo6Se6. https://doi.org/10.1103/physrevb.98.140502

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