Ubiquitous formation of bulk Dirac cones and topological surface states from a single orbital manifold in transition-metal dichalcogenides
Date
01/2018Author
Grant ID
PLP-2015-144
2016-006
EP/M023427/1
EP/I031014/1
UF120096
Metadata
Show full item recordAbstract
Transition-metal dichalcogenides (TMDs) are renowned for their rich and varied bulk properties, while their single-layer variants have become one of the most prominent examples of two-dimensional materials beyond graphene. Their disparate ground states largely depend on transition metal d-electron-derived electronic states, on which the vast majority of attention has been concentrated to date. Here, we focus on the chalcogen-derived states. From density-functional theory calculations together with spin- and angle-resolved photoemission, we find that these generically host a coexistence of type-I and type-II three-dimensional bulk Dirac fermions as well as ladders of topological surface states and surface resonances. We demonstrate how these naturally arise within a single p-orbital manifold as a general consequence of a trigonal crystal field, and as such can be expected across a large number of compounds. Already, we demonstrate their existence in six separate TMDs, opening routes to tune, and ultimately exploit, their topological physics.
Citation
Bahramy , M S , Clark , O J , Yang , B-J , Feng , J , Bawden , L , Riley , J M , Markovic , I , Mazzola , F , Sunko , V , Biswas , D , Cooil , S P , Jorge , M , Wells , J W , Leandersson , M , Balasubramanian , T , Fujii , J , Vobornik , I , Rault , J , Kim , T K , Hoesch , M , Okawa , K , Asakawa , M , Sasagawa , T , Eknapakul , T , Meevasana , W & King , P D C 2018 , ' Ubiquitous formation of bulk Dirac cones and topological surface states from a single orbital manifold in transition-metal dichalcogenides ' , Nature Materials , vol. 17 , no. 1 , pp. 21-28 . https://doi.org/10.1038/nmat5031
Publication
Nature Materials
Status
Peer reviewed
ISSN
1476-1122Type
Journal article
Rights
© 2017 Macmillan Publishers Ltd. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1038/nmat5031
Description
Funding: Leverhulme Trust, the Engineering and Physical Sciences Research Council, UK (Grant Nos. EP/M023427/1 and EP/I031014/1), the Royal Society, OJC, LB, JMR and VS acknowledge EPSRC for PhD studentship support through grant Nos. EP/K503162/1, EP/G03673X/1, EP/L505079/1, and EP/L015110/1.Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.