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arXiv · 1903.00509

Fermi-arc diversity on surface terminations of the magnetic Weyl semimetal Co3Sn2S2

Noam Morali·Rajib Batabyal·Pranab Kumar Nag·Enke Liu·Qiunan Xu·Yan Sun·Binghai Yan·Claudia Felser·Nurit Avraham·Haim Beidenkopf
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Abstract

Bulk-surface correspondence in Weyl semimetals assures the formation of topological "Fermi-arc" surface bands whose existence is guaranteed by bulk Weyl nodes. By investigating three distinct surface terminations of the ferromagnetic semimetal Co3Sn2S2 we verify spectroscopically its classification as a time reversal symmetry broken Weyl semimetal. We show that the distinct surface potentials imposed by three different terminations modify the Fermi-arc contour and Weyl node connectivity. On the Sn surface we identify intra-Brillouin zone Weyl node connectivity of Fermi-arcs, while on Co termination the connectivity is across adjacent Brillouin zones. On the S surface Fermi-arcs overlap with non-topological bulk and surface states that ambiguate their connectivity and obscure their exact identification. By these we resolve the topologically protected electronic properties of a Weyl semimetal and its unprotected ones that can be manipulated and engineered.

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Noam Morali, Rajib Batabyal, Pranab Kumar Nag, Enke Liu, Qiunan Xu, Yan Sun, Binghai Yan, Claudia Felser, Nurit Avraham, Haim Beidenkopf. 2019-03-01. Fermi-arc diversity on surface terminations of the magnetic Weyl semimetal Co3Sn2S2. https://doi.org/10.1126/science.aav2334

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