263 research outputs found
The hot pick-up technique for batch assembly of van der Waals heterostructures
The assembly of individual two-dimensional materials into van der Waals
heterostructures enables the construction of layered three-dimensional
materials with desirable electronic and optical properties. A core problem in
the fabrication of these structures is the formation of clean interfaces
between the individual two-dimensional materials which would affect device
performance. We present here a technique for the rapid batch fabrication of van
der Waals heterostructures, demonstrated by the controlled production of 22
mono-, bi- and trilayer graphene stacks encapsulated in hexagonal boron nitride
with close to 100% yield. For the monolayer devices we found semiclassical mean
free paths up to 0.9 micrometer, with the narrowest samples showing clear
indications of the transport being affected by boundary scattering. The
presented method readily lends itself to fabrication of van der Waals
heterostructures in both ambient and controlled atmospheres, while the ability
to assemble pre-patterned layers paves the way for complex three-dimensional
architectures.Comment: 32 pages, 6 figures, 34 references, 14 supplementary figure
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The impact of autonomy and organisational relationships on subsidiary employment of skilled labour
The paper develops a conceptual model on relationship between the strategic development of subsidiaries, in developed economies, and the development of higher valued operations that leads to increased employment of skilled labour. A concept of effective autonomy is developed in the paper. Effective autonomy is conceived as the ability of the subsidiary to implement and finance its desired increase in skilled labour. The interrelated effects between effective autonomy and intra and inter organisational relationships and employment of skilled labour are found to be uncertain because effective autonomy can be supportive of the development of intra and inter organisational relationships that requires a higher proportion of skilled labour, but effective autonomy can lead to deterioration in intra-organisational relationships thereby leading to a more peripheral role played by the subsidiary thus lowering the need for skilled employment. The conceptual model is based on changes in effective autonomy and intra and inter organisational relationships and is therefore set in the context of the evolution of the development of subsidiaries
Quantitative optical mapping of two-dimensional materials
The pace of two-dimensional materials (2DM) research has been greatly accelerated by the ability to identify exfoliated thicknesses down to a monolayer from their optical contrast. Since this process requires time-consuming and error-prone manual assignment to avoid false-positives from image features with similar contrast, efforts towards fast and reliable automated assignments schemes is essential. We show that by modelling the expected 2DM contrast in digitally captured images, we can automatically identify candidate regions of 2DM. More importantly, we show a computationally-light machine vision strategy for eliminating false-positives from this set of 2DM candidates through the combined use of binary thresholding, opening and closing filters, and shape-analysis from edge detection. Calculation of data pyramids for arbitrarily high-resolution optical coverage maps of two-dimensional materials produced in this way allows the real-time presentation and processing of this image data in a zoomable interface, enabling large datasets to be explored and analysed with ease. The result is that a standard optical microscope with CCD camera can be used as an analysis tool able to accurately determine the coverage, residue/contamination concentration, and layer number for a wide range of presented 2DMs
Conductance quantization suppression in the quantum Hall regime
Conductance quantization is the hallmark of non-interacting confined systems. The authors show that the quantization in graphene nanoconstrictions with low edge disorder is suppressed in the quantum Hall regime. This is explained by the addition of new conductance channels due to electrostatic screening
Motivation and Knowledge Sharing through Social Media within Danish Organizations
Part 3: Creating Value through ApplicationsInternational audienceBased on an empirical quantitative study, this article investigates employee motivation in Danish companies and aims at determining which factors affect employeesâ knowledge sharing through social media in a working environment. Our findings pinpoint towards the potential social media have for enhancing internal communication, knowledge sharing and collaboration in organizations, but the adoption is low, at this point, due to mainly organizational and individual factors. Technological factors do not seem to affect employeesâ motivation for knowledge sharing as much as previous research has found, but it is the influence from the combination of individual and organizational factors, which affect the adoption of the platforms. A key finding in the study is that knowledge sharing is not a âsocial dilemmaâ as previous studies have found. The study shows a positive development in employeesâ willingness to share knowledge, because knowledge sharing is considered more beneficial than to hoard it
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