Schwierz F.,TU Ilmenau
Proceedings of the IEEE | Year: 2013
Graphene is a relatively new material with unique properties that holds promise for electronic applications. Since 2004, when the first graphene samples were intentionally fabricated, the worldwide research activities on graphene have literally exploded. Apart from physicists, also device engineers became interested in the new material and soon the prospects of graphene in electronics have been considered. For the most part, the early discussions on the potential of graphene had a prevailing positive mood, mainly based on the high carrier mobilities observed in this material. This has repeatedly led to very optimistic assessments of the potential of graphene transistors and to an underestimation of their problems. In this paper, we discuss the properties of graphene relevant for electronic applications, examine its advantages and problems, and summarize the state of the art of graphene transistors. © 1963-2012 IEEE.
Kelly D.P.,TU Ilmenau
Journal of the Optical Society of America A: Optics and Image Science, and Vision | Year: 2014
In this paper, we address the problem of calculating Fresnel diffraction integrals using a finite number of uniformly spaced samples. General and simple sampling rules of thumb are derived that allow the user to calculate the distribution for any propagation distance. It is shown how these rules can be extended to fast-Fouriertransform- based algorithms to increase calculation efficiency. A comparison with other theoretical approaches is made. © 2014 Optical Society of America.
Heinicke C.,TU Ilmenau
Experiments in Fluids | Year: 2013
Velocity measurements inside metal melt flows are important for many laboratory and industrial applications in metallurgy but remain experimentally challenging. Only few techniques are viable for the measurement of mean flow velocities inside hot and aggressive materials. One of them is the previously studied electromagnetic contact-free Lorentz force velocimetry. However, the desire to resolve velocities spatially has not been satisfied so far. In the work presented here, spatial resolution is reached with a Lorentz force flow meter (LFF) by implementing a permanent magnet whose dimensions are significantly smaller than that of the flow under investigation. It is shown on a straight square duct flow that such a flow meter is capable of distinguishing obstacles in the flow and the resulting modified flow structures. The spatial resolution of the LFF is demonstrated to be at least on the order of 3 cm with a 1 cm magnet cube. © 2013 Springer-Verlag Berlin Heidelberg.
Schwierz F.,TU Ilmenau
Nature Nanotechnology | Year: 2010
Graphene has changed from being the exclusive domain of condensed-matter physicists to being explored by those in the electron-device community. In particular, graphene-based transistors have developed rapidly and are now considered an option for post-silicon electronics. However, many details about the potential performance of graphene transistors in real applications remain unclear. Here I review the properties of graphene that are relevant to electron devices, discuss the trade-offs among these properties and examine their effects on the performance of graphene transistors in both logic and radiofrequency applications. I conclude that the excellent mobility of graphene may not, as is often assumed, be its most compelling feature from a device perspective. Rather, it may be the possibility of making devices with channels that are extremely thin that will allow graphene field-effect transistors to be scaled to shorter channel lengths and higher speeds without encountering the adverse short-channel effects that restrict the performance of existing devices. Outstanding challenges for graphene transistors include opening a sizeable and well-defined bandgap in graphene, making large-area graphene transistors that operate in the current-saturation regime and fabricating graphene nanoribbons with well-defined widths and clean edges. © 2010 Macmillan Publishers Limited. All rights reserved.
Agency: Cordis | Branch: H2020 | Program: MSCA-RISE | Phase: MSCA-RISE-2014 | Award Amount: 670.50K | Year: 2015
Innovation technologies in ground vehicle engineering require strong interdisciplinary and intersectoral investigations with an international dimension. In this context the project EVE proposes sustainable approach based on intensive staff exchange that leads to collaborative research and training between universities and industrial organizations from Germany, Belgium, Spain, Sweden, The Netherlands, South Africa, and the USA. The project includes basic and applied research, development design, experimentations, networking, and dissemination and exploitation activities. The research objectives are focused on the development of (i) experimental tyre database that can be used in the design of new chassis control systems and subjected to inclusion into Horizon 2020 pilot on Open Research Data, (ii) advanced models of ground vehicles and automotive subsystems for real-time applications, and (iii) novel integrated chassis control methods. It will lead to development and improvement of innovative vehicle components such as (i) an integrated chassis controller targeting simultaneous improvements in safety, energy efficiency and driving comfort, (ii) new hardware subsystems for brakes, active suspension and tyre pressure control for on-road and off-road mobility, and (iii) remote network-distributed vehicle testing technology for integrated chassis systems. The project targets will be achieved with intensive networking measures covering (i) knowledge transfer and experience sharing between participants from academic and non-academic sectors and (ii) professional advancement of the consortium members through intersectoral and international collaboration and secondments. The project EVE is fully consistent with the targets of H2020-MSCA-RISE programme and will provide excellent opportunities for personal career development of staff and will lead to creation of a strong European and international research group to create new hi-tech ground vehicle systems.