In:
Nature Communications, Springer Science and Business Media LLC, Vol. 8, No. 1 ( 2017-10-18)
Abstract:
Topological nodal line semimetals, a novel quantum state of materials, possess topologically nontrivial valence and conduction bands that touch at a line near the Fermi level. The exotic band structure can lead to various novel properties, such as long-range Coulomb interaction and flat Landau levels. Recently, topological nodal lines have been observed in several bulk materials, such as PtSn 4 , ZrSiS, TlTaSe 2 and PbTaSe 2 . However, in two-dimensional materials, experimental research on nodal line fermions is still lacking. Here, we report the discovery of two-dimensional Dirac nodal line fermions in monolayer Cu 2 Si based on combined theoretical calculations and angle-resolved photoemission spectroscopy measurements. The Dirac nodal lines in Cu 2 Si form two concentric loops centred around the Γ point and are protected by mirror reflection symmetry. Our results establish Cu 2 Si as a platform to study the novel physical properties in two-dimensional Dirac materials and provide opportunities to realize high-speed low-dissipation devices.
Type of Medium:
Online Resource
ISSN:
2041-1723
DOI:
10.1038/s41467-017-01108-z
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2017
detail.hit.zdb_id:
2553671-0
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