Mini-Dirac cones in the band structure of a copper intercalated epitaxial graphene superlattice
(2016) In 2D Materials 3(3).- Abstract
The electronic band structure of an epitaxial graphene superlattice, generated by intercalating a monolayer of Cu atoms, is directly imaged by angle-resolved photoelectron spectroscopy. The 3.2 nm lateral period of the superlattice is induced by a varying registry between the graphene honeycomb and the Cu atoms as imposed by the heteroepitaxial interface Cu/SiC. The carbon atoms experience a lateral potential across the supercell of an estimated value of about 65 meV. The potential leads to strong energy renormalization in the band structure of the graphene layer and the emergence of mini-Dirac cones. The mini-cones' band velocity is reduced to about half of graphene's Fermi velocity. Notably, the ordering of the interfacial Cu atoms... (More)
The electronic band structure of an epitaxial graphene superlattice, generated by intercalating a monolayer of Cu atoms, is directly imaged by angle-resolved photoelectron spectroscopy. The 3.2 nm lateral period of the superlattice is induced by a varying registry between the graphene honeycomb and the Cu atoms as imposed by the heteroepitaxial interface Cu/SiC. The carbon atoms experience a lateral potential across the supercell of an estimated value of about 65 meV. The potential leads to strong energy renormalization in the band structure of the graphene layer and the emergence of mini-Dirac cones. The mini-cones' band velocity is reduced to about half of graphene's Fermi velocity. Notably, the ordering of the interfacial Cu atoms can be reversibly blocked by mild annealing. The superlattice indeed disappears at∼220 °C.
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- author
- Forti, S. ; Stöhr, A. ; Zakharov, A. A. LU ; Coletti, C. ; Emtsev, K. V. and Starke, U.
- organization
- publishing date
- 2016-07-05
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Epitaxial graphene, Graphene, Intercalation, Photoemission, Superlattice
- in
- 2D Materials
- volume
- 3
- issue
- 3
- article number
- 035003
- publisher
- IOP Publishing
- external identifiers
-
- scopus:84992427939
- wos:000389710800001
- ISSN
- 2053-1583
- DOI
- 10.1088/2053-1583/3/3/035003
- language
- English
- LU publication?
- yes
- id
- 7d76cb60-7a98-4b48-9754-e33dc08ba92f
- date added to LUP
- 2017-01-12 14:31:02
- date last changed
- 2024-09-22 06:09:43
@article{7d76cb60-7a98-4b48-9754-e33dc08ba92f, abstract = {{<p>The electronic band structure of an epitaxial graphene superlattice, generated by intercalating a monolayer of Cu atoms, is directly imaged by angle-resolved photoelectron spectroscopy. The 3.2 nm lateral period of the superlattice is induced by a varying registry between the graphene honeycomb and the Cu atoms as imposed by the heteroepitaxial interface Cu/SiC. The carbon atoms experience a lateral potential across the supercell of an estimated value of about 65 meV. The potential leads to strong energy renormalization in the band structure of the graphene layer and the emergence of mini-Dirac cones. The mini-cones' band velocity is reduced to about half of graphene's Fermi velocity. Notably, the ordering of the interfacial Cu atoms can be reversibly blocked by mild annealing. The superlattice indeed disappears at∼220 °C.</p>}}, author = {{Forti, S. and Stöhr, A. and Zakharov, A. A. and Coletti, C. and Emtsev, K. V. and Starke, U.}}, issn = {{2053-1583}}, keywords = {{Epitaxial graphene; Graphene; Intercalation; Photoemission; Superlattice}}, language = {{eng}}, month = {{07}}, number = {{3}}, publisher = {{IOP Publishing}}, series = {{2D Materials}}, title = {{Mini-Dirac cones in the band structure of a copper intercalated epitaxial graphene superlattice}}, url = {{http://dx.doi.org/10.1088/2053-1583/3/3/035003}}, doi = {{10.1088/2053-1583/3/3/035003}}, volume = {{3}}, year = {{2016}}, }