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

By Noam Morali, R. Batabyal, P. Nag, Enke Liu, Qiunan Xu, Yan Sun, Binghai Yan, Claudia Felser, N. Avraham, H. Beidenkopf. Science, 2019

612 citations recorded by the source corpus.

Magnetic Weyl semimetals Weyl semimetals (WSMs)—materials that host exotic quasiparticles called Weyl fermions—must break either spatial inversion or time-reversal symmetry. A number of WSMs that break inversion symmetry have been identified, but showing unambiguously that a material is a time-reversal-breaking WSM is tricky. Three groups now provide spectroscopic evidence for this latter state in magnetic materials (see the Perspective by da Silva Neto). Belopolski et al. probed the material Co2MnGa using angle-resolved photoemission spectroscopy, revealing exotic drumhead surface states. Using the same technique, Liu et al. studied the material Co3Sn2S2, which was complemented by the scanning tunneling spectroscopy measurements of Morali et al. These magnetic WSM states provide an ideal setting for exotic transport effects. Science, this issue p. 1278, p. 1282, p. 1286; see also p. 1248 Photoemission and scanning tunneling spectroscopies provide direct evidence for the existence of magnetic Weyl semimetals. Bulk–surface correspondence in Weyl semimetals ensures 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 tin (Sn) surface, we identify intra–Brillouin zone Weyl node connectivity of Fermi arcs, whereas on cobalt (Co) termination, the connectivity is across adjacent Brillouin zones. On the sulfur (S) surface, Fermi arcs overlap with nontopological bulk and surface states. We thus resolve both topologically protected and nonprotected electronic properties of a Weyl semimetal.

Subfields: Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/4980e6c30bf2fcd7fffa21ca16952d9dad0063c0

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

1. Cheng Guo
2. Bo Zhao
3. V. Asadchy
4. Chaoxing Liu
5. Cui-Zu Chang
6. Shanhui Fan
7. Mazhar N. Ali
8. Allan H. MacDonald

In Electronic, Optical and Magnetic Materials

1. Shanhui Fan
2. Allan H. MacDonald

In Materials Chemistry

1. Chaoxing Liu
2. Cui-Zu Chang
3. Shanhui Fan
4. Mazhar N. Ali
5. Cheng Guo
6. Bo Zhao
7. V. Asadchy
8. Allan H. MacDonald

Citations in the corpus

• Quantum states and intertwining phases in kagome materials (2023, background): “13,14), Dirac points and flat bands in FeSn (ref.”
• Light control with Weyl semimetals (2022, background): “Later, magnetic Weyl semimetals that break time-reversal symmetry have also been discovered [42, 43, 44].”
• Angle-resolved photoemission studies of quantum materials (2020, neutral): “…evidence for Weyl semimetals with broken time-reversal symmetry has been more elusive (Kuroda et al., 2017), though recently there was compelling evidence from ARPES and STM that Co3Sn2S2 is a ferromagnetic Weyl semimetal with three pairs of Weyl nodes (Liu et al., 2019a; Morali et al., 2019).”
• Superconductivity in the Z2 kagome metal KV3Sb5 (2020, neutral): “[36] N.”
• Colloquium : Quantum anomalous Hall effect (2022, background): “Following this idea, a number of intrinsic magnetic materials have been proposed, including HgCr2Se4 (Xu et al., 2011), Co3Sn2S2 (Liu et al., 2019a; Morali et al., 2019), Mn2Sn (Kuroda et al., 2017), and Co2MnGa (Belopolski et al., 2019).”