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arXiv · 2105.07515

Experimental observation and spin texture of Dirac node arcs in tetradymite topological metals

J. Dai·E. Frantzeskakis·N. Aryal·K. -W. Chen·F. Fortuna·J. E. Rault·P. Le Fèvre·L. Balicas·K. Miyamoto·T. Okuda·E. Manousakis·R. E. Baumbach·A. F. Santander-Syro
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Abstract

We report the observation of a non-trivial spin texture in Dirac node arcs, novel topological objects formed when Dirac cones of massless particles extend along an open one-dimensional line in momentum space. We find that such states are present in all the compounds of the tetradymite M$_2$Te$_2$X family (M$=$Ti, Zr or Hf and X$=$P or As), regardless of the weak or strong character of the topological invariant. The Dirac node arcs in tetradymites are thus the simplest possible, textbook example, of a type-I Dirac system with a single spin-polarized node arc.

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J. Dai, E. Frantzeskakis, N. Aryal, K. -W. Chen, F. Fortuna, J. E. Rault, P. Le Fèvre, L. Balicas, K. Miyamoto, T. Okuda, E. Manousakis, R. E. Baumbach, A. F. Santander-Syro. 2021-05-16. Experimental observation and spin texture of Dirac node arcs in tetradymite topological metals. https://doi.org/10.1103/physrevlett.126.196407

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