| 1. |
- Forti, S., et al.
(författare)
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Large-area homogeneous quasifree standing epitaxial graphene on SiC(0001): Electronic and structural characterization
- 2011
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Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 84:12
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Tidskriftsartikel (refereegranskat)abstract
- The growth of epitaxial graphene on SiC has been identified as one of the most promising techniques to produce graphene for electronic applications. In this paper, we present a systematic study of the electronic and structural properties of large-area quasifree standing epitaxial monolayer graphene grown on top of the SiC(0001) surface. For this purpose, we combine the thermal treatment of SiC in Ar atmosphere to achieve a homogeneous coverage of the surface with the hydrogen intercalation process, which leads to the removal of the interaction between the substrate and the carbon layer. The band structure in the vicinity of the (K) over bar point is measured using high-resolution angle-resolved photoelectron spectroscopy. A detailed analysis of the quasiparticle dynamics reveals a renormalization of the band velocity estimated to about 3% at energies around 200 meV below the Fermi level, which mainly originates from electron-phonon interaction. Further analysis of the momentum distribution curves leads to the formulation of a model for the doping reduction in such a system in the course of sample annealing above 650 degrees C. The uniformity and homogeneity of the graphene is demonstrated by means of low-energy electron microscopy (LEEM). Microphotoelectron spectroscopy data confirm the high structural quality and homogeneity of the quasifree standing graphene. Using LEEM and scanning tunneling microscopy, we demonstrate that the hydrogen desorption at elevated temperatures of approximately 750 degrees C sets in on the graphene terraces rather than via the step edges.
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| 4. |
- Baringhaus, J., et al.
(författare)
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Bipolar gating of epitaxial graphene by intercalation of Ge
- 2014
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 104:26
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Tidskriftsartikel (refereegranskat)abstract
- In this study, the ambivalent behavior of Ge intercalation is studied by means of scanning tunneling microscopy and spectroscopy as well as local 4-point probe transport measurements. In quantitative agreement with angle-resolved photoemission experiments, both p-and n-type doped graphene areas and their doping level were identified by local spectroscopy. The p-doped areas appear higher by 2 angstrom with respect to the n-doped areas suggesting incorporation of thicker Ge-layers accompanied by a modified coupling to the initial SiC-surface. Furthermore, the sheet resistance was measured on each of the patches separately. The intrinsic imbalance between the carrier types in the different areas is well reflected by the transport study. The process of intercalation does not affect the transport properties in comparison to pristine graphene pointing to a sufficient homogeneity of the decoupled graphene layer. Transport measurements across chemically gated pn-junctions reveal increased resistances, possibly due to enlarged tunneling barriers. (C) 2014 AIP Publishing LLC.
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| 5. |
- Coletti, C., et al.
(författare)
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Large area quasi-free standing monolayer graphene on 3C-SiC(111)
- 2011
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 99:8
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Tidskriftsartikel (refereegranskat)abstract
- Large scale, homogeneous quasi-free standing monolayer graphene is obtained on cubic silicon carbide, i.e., the 3C-SiC(111) surface, which represents an appealing and cost effective platform for graphene growth. The quasi-free monolayer is produced by intercalation of hydrogen under the interfacial, (6 root 3 x 6 root 3)R30 degrees-reconstructed carbon layer. After intercalation, angle resolved photoemission spectroscopy reveals sharp linear pi-bands. The decoupling of graphene from the substrate is identified by x-ray photoemission spectroscopy and low energy electron diffraction. Atomic force microscopy and low energy electron microscopy demonstrate that homogeneous monolayer domains extend over areas of hundreds of square-micrometers. (C) 2011 American Institute of Physics. [doi:10.1063/1.3618674]
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| 6. |
- 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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| 9. |
- 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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| 10. |
- 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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