26. |
- Coletti, C., et al.
(författare)
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Revealing the electronic band structure of trilayer graphene on SiC: An angle-resolved photoemission study
- 2013
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Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 88:15
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Tidskriftsartikel (refereegranskat)abstract
- In recent times, trilayer graphene has attracted wide attention owing to its stacking and electric-field-dependent electronic properties. However, a direct and well-resolved experimental visualization of its band structure has not yet been reported. In this paper, we present angle-resolved photoemission spectroscopy data which show with high resolution the electronic band structure of trilayer graphene obtained on alpha-SiC(0001) and beta-SiC(111) via hydrogen intercalation. Electronic bands obtained from tight-binding calculations are fitted to the experimental data to extract the interatomic hopping parameters for Bernal and rhombohedral stacked trilayers. Low-energy electron microscopy measurements demonstrate that the trilayer domains extend over areas of tens of square micrometers, suggesting the feasibility of exploiting this material in electronic and photonic devices. Furthermore, our results suggest that, on SiC substrates, the occurrence of a rhombohedral stacked trilayer is significantly higher than in natural bulk graphite.
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27. |
- Forti, S., et al.
(författare)
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Mini-Dirac cones in the band structure of a copper intercalated epitaxial graphene superlattice
- 2016
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Ingår i: 2D Materials. - : IOP Publishing. - 2053-1583. ; 3:3
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Tidskriftsartikel (refereegranskat)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 can be reversibly blocked by mild annealing. The superlattice indeed disappears at∼220 °C.
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28. |
- Hellberg, C., et al.
(författare)
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Evidence and evidence gaps in assessments and interventions in areas related to social work research and practice - an overview of four evidence maps
- 2023
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Ingår i: European Journal of Social Work. - : Informa UK Limited. - 1369-1457 .- 1468-2664. ; 26:5
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Tidskriftsartikel (refereegranskat)abstract
- This overview of four evidence maps is based on systematic reviews of assessment and interventions in social work practice. The aim was to investigate the evidence and evidence gaps within four important areas for social work research and practice. Descriptive data on search strategies and domains were collected from four evidence maps, on Social Assistance, Substance Dependence, Care for older adults respectively for persons with disabilities. The scientific quality and scientific evidence were assessed. Key findings were summarised by analyzing and discussing common and specific elements in the evidence maps. The overview was undertaken in close collaboration between researchers with expertise in the field and a government agency. The overview identified both evidence and evidence gaps with respect to effects and experiences of interventions and assessment methods in four evidence maps. Evidence maps provide a comprehensive picture of the state of social services research and can thereby be of use to both researchers and practitioners, and in the production of evidence based social work.
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29. |
- Kotschik, Pia, et al.
(författare)
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The upcoming European Soil Monitoring Law : An effective instrument for the protection of terrestrial ecosystems?
- 2024
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Ingår i: Integrated Environmental Assessment and Management. - : John Wiley & Sons. - 1551-3777 .- 1551-3793. ; 20:2, s. 316-321
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Tidskriftsartikel (refereegranskat)abstract
- Soils are a precious resource consistently placed under several threats, and urgently, in need of protection within a regulatory framework at the European level. Soils are central to the provision of environmental services as well as human existence on earth. The need to protect soil has been identified by several recent European strategies and fortunately, a specific European Regulation for soil protection is on the way - the European Soil Monitoring Law (formerly: Soil Health Law). However, efforts need to ensure that the upcoming Soil Monitoring law closes gaps between existing regulations for chemicals and acknowledges current European strategies for environmental protection and sustainability. This brief communication started from a fruitful discussion among SETAC Global Soils Interest Group members on a recent public consultation on the newly proposed Soil Monitoring Law of the European Commission and highlights critical points focusing on the chemical pollution of soils. We emphasise urgent needs such as the essential definition of a 'healthy state' of soils, the implementation of a suitable set of indicators and quality standards for the description of physical, chemical and biological states of soils, the enforcement of the 'polluters pay's' principle and the establishment of a European wide monitoring program. Results from monitoring need to be fed back into regulatory frameworks, including the regulation of chemicals. Guidance documents for the risk assessment of chemicals are outdated and need to be updated. Finally, actions need to be taken to foster healthy soils, stop biodiversity decline and ensure the functioning of ecosystem services for future generations.
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30. |
- Riedl, C., et al.
(författare)
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Precise in situ thickness analysis of epitaxial graphene layers on SiC(0001) using low-energy electron diffraction and angle resolved ultraviolet photoelectron spectroscopy
- 2008
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 93:3
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Tidskriftsartikel (refereegranskat)abstract
- We demonstrate an easy and practical method for the thickness analysis of epitaxial graphene on SiC(0001) that can be applied continuously during the preparation procedure. Fingerprints in the spot intensity spectra in low energy electron diffraction (LEED) allow for the exact determination of the number of layers for the first three graphene layers. The LEED data have been correlated with the electronic bandstructure around the (K) over bar -point of the graphene Brillouin zone as investigated by laboratory based angle resolved ultraviolet photoelectron spectroscopy using He II excitation. The morphology and homogeneity of the graphene layers can be analyzed by low energy electron microscopy. (C) 2008 American Institute of Physics.
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31. |
- Schädlich, Philip, et al.
(författare)
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Domain Boundary Formation Within an Intercalated Pb Monolayer Featuring Charge-Neutral Epitaxial Graphene
- 2023
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Ingår i: Advanced Materials Interfaces. - 2196-7350. ; 10:27
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Tidskriftsartikel (refereegranskat)abstract
- The synthesis of new graphene-based quantum materials by intercalation is an auspicious approach. However, an accompanying proximity coupling depends crucially on the structural details of the new heterostructure. It is studied in detail the Pb monolayer structure after intercalation into the graphene buffer layer on the SiC(0001) interface by means of photoelectron spectroscopy, x-ray standing waves, and scanning tunneling microscopy. A coherent fraction close to unity proves the formation of a flat Pb monolayer on the SiC surface. An interlayer distance of 3.67 Å to the suspended graphene underlines the formation of a truly van der Waals heterostructure. The 2D Pb layer reveals a quasi ten-fold periodicity due to the formation of a grain boundary network, ensuring the saturation of the Si surface bonds. Moreover, the densely-packed Pb layer also efficiently minimizes the doping influence by the SiC substrate, both from the surface dangling bonds and the SiC surface polarization, giving rise to charge-neutral monolayer graphene. The observation of a long-ranged ((Formula presented.)) reconstruction on the graphene lattice at tunneling conditions close to Fermi energy is most likely a result of a nesting condition to be perfectly fulfilled.
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32. |
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33. |
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34. |
- Starke, Mikaela, 1960, et al.
(författare)
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Parenting with disabilities: Experiences from implementing a parenting support programme in Sweden
- 2013
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Ingår i: Journal of Intellectual Disabilities. - : SAGE Publications. - 1744-6295 .- 1744-6309. ; 17:2, s. 145-156
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Tidskriftsartikel (refereegranskat)abstract
- This article reports on the initial stages of implementing an Australian-based education programme for parents with intellectual disabilities (IDs) in Sweden. The clinical utility of the programme, Parenting Young Children (PYC), in the new country context is explored through Swedish professionals' experiences in learning and using it. Study participants found PYC well suited for use in their working environment. Most of them reported the programme to have strengthened their work with parents. The programme was seen as benefiting both the study participants in their work with parents with IDs and these parents themselves, and its structure and content were found to be helpful in several ways. The checklists forming part of PYC were considered useful, but their purpose was sometimes misunderstood. The reported study helps to identify what is needed to improve the translation of the programme into the new country context, to promote appropriate and more effective use of programme materials. © 2013 The Author(s).
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35. |
- Stöhr, Alexander, et al.
(författare)
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Graphene Ribbon Growth on Structured Silicon Carbide
- 2017
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Ingår i: Annalen der Physik. - : Wiley. - 0003-3804. ; 529:11
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Tidskriftsartikel (refereegranskat)abstract
- Structured Silicon Carbide was proposed to be an ideal template for the production of arrays of edge specific graphene nanoribbons (GNRs), which could be used as a base material for graphene transistors. We prepared periodic arrays of nanoscaled stripe-mesas on SiC surfaces using electron beam lithography and reactive ion etching. Subsequent epitaxial graphene growth by annealing is differentiated between the basal-plane mesas and the faceting stripe walls as monitored by means of atomic force microscopy (AFM). Microscopic low energy electron diffraction (μ-LEED) revealed that the graphene ribbons on the facetted mesa side walls grow in epitaxial relation to the basal-plane graphene with an armchair orientation at the facet edges. The π-band system of the ribbons exhibits linear bands with a Dirac like shape corresponding to monolayer graphene as identified by angle-resolved photoemission spectroscopy (ARPES).
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36. |
- van Lankveld, JJDM, et al.
(författare)
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Women's sexual pain disorders
- 2010
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Ingår i: The journal of sexual medicine. - : Oxford University Press (OUP). - 1743-6109 .- 1743-6095. ; 7:11 Pt 2, s. 615-631
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Tidskriftsartikel (refereegranskat)
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37. |
- Virojanadara, Chariya, et al.
(författare)
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Silicon adatom chains and one-dimensionally confined electrons on 4H-SiC(1-102): The (2x1) reconstruction
- 2008
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Ingår i: Surface Science. - : Elsevier. - 0039-6028 .- 1879-2758. ; 602:22, s. 3506-3509
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Tidskriftsartikel (refereegranskat)abstract
- The electronic and atomic structure of the 4H-SiC surface was investigated. Photoemission data indicate that the surface contains about 2 Si layers on top of the bulk layers. Scanning tunneling microscopy images show that these adlayers are terminated by an ordered array of adatom chains separated by the unit cell size. An electronic surface state located at a binding energy of 0.8 eV shows one-dimensional confinement with dispersion only along the chains. Based on the experimental observations, a tentative (2 × 1) surface model is derived with the surface terminated by alternating chains of Si adatoms and Si dimers in between.
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