Freiburg, Germany
Freiburg, Germany

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Agency: Cordis | Branch: FP7 | Program: BSG-SME | Phase: SME-1 | Award Amount: 1.47M | Year: 2009

Cancer is responsible for 25% of all deaths in Europe and is the biggest killer of people aged 45-64 and 1 in 3 EU citizens can expect to deal with a cancer episode in their lifetime. The cost of treatment in Europe is over 50 billion and fighting the disease is a major EU priority. Radiotherapy is in the most used treatment and recent advances such as IMRT and other conformal radiotherapy solutions are significantly improving treatment success rates. However, existing dosimetry techniques are not capable of delivering the high resolution, tissue equivalence and high speed measurements required for IMRT calibration. This leads to lengthy set-up times, seriously limiting the number of patients that can be treated. Radi-Cal will look to build on recent breakthroughs in CVD diamond technology (realised with EC support) and develop an innovative, high resolution, monolithic 2D CVD diamond array based dosimeter which will deliver the levels of performance required by IMRT and other conformal radiotherapy solutions whilst reducing calibration and set-up time by a factor of 7, thereby allowing more patients access to conformal radiotherapy which will significantly improve treatment success rates. The science and technology required to do this will be challenging, however our consortium comprises some of Europes leading research and industrial companies. Our innovations are in CVD diamond structure and contacts for a 2D sensor; 2D array sensor fabrication and radiation shielding; ultra-low 2D array readout electronics. The market potential for such a product is over 130 million. Although European SMEs dominate the market for radiotherapy dosimetry systems this situation is being seriously threatened by large non-EU enterprises such as Varian, who are now targeting dosimetry. As European SMEs, we urgently need to beat our competition to an IMRT dosimetry solution to protect our market and enable us to compete against internationally.


Rath P.,Karlsruhe Institute of Technology | Nebel C.,Fraunhofer Institute for Applied Solid State Physics | Wild C.,Fraunhofer Institute for Applied Solid State Physics | Wild C.,Diamond Materials GmbH | Pernice W.H.P.,Karlsruhe Institute of Technology
2013 Conference on Lasers and Electro-Optics, CLEO 2013 | Year: 2013

We realize nanophotonic circuits on large area, microcrystalline diamond-on-insulator substrates, including on-chip interferometers and cavities. Ring resonators show Q-factors up to 11,000 at 1550nm, corresponding to propagation loss of 4.7dB/mm. © 2013 The Optical Society.


Lebedev V.,Fraunhofer Institute for Applied Solid State Physics | Iankov D.,Fraunhofer Institute for Applied Solid State Physics | Iankov D.,Albert Ludwigs University of Freiburg | Heidrich N.,Fraunhofer Institute for Applied Solid State Physics | And 6 more authors.
Journal of Micromechanics and Microengineering | Year: 2014

In this work, we report on the electro-mechanical studies of high-Q spherical oscillators designed to operate in radio-frequency circuits. Resonating composite spheres, consisting of a silicon core and a thick nanodiamond shell, were studied by laser vibrometry in order to obtain mechanical quality factors and identify the resonant frequencies and eigenmodes of the system. Finite element method simulations were used to analyze and confirm the experimental data. Additionally, reflection/transmission measurements were carried out on capacitively coupled spheres in order to evaluate the electrical parameters of the system. The main aim of these investigations was to evaluate the potential of diamond-based spherical resonators to be used in modern communication devices. © 2014 IOP Publishing Ltd.


Rath P.,Karlsruhe Institute of Technology | Khasminskaya S.,Karlsruhe Institute of Technology | Nebel C.,Fraunhofer Institute for Applied Solid State Physics | Wild C.,Fraunhofer Institute for Applied Solid State Physics | And 2 more authors.
Nature Communications | Year: 2013

Diamond offers unique material advantages for the realization of micro- and nanomechanical resonators because of its high Young's modulus, compatibility with harsh environments and superior thermal properties. At the same time, the wide electronic bandgap of 5.45 eV makes diamond a suitable material for integrated optics because of broadband transparency and the absence of free-carrier absorption commonly encountered in silicon photonics. Here we take advantage of both to engineer full-scale optomechanical circuits in diamond thin films. We show that polycrystalline diamond films fabricated by chemical vapour deposition provide a convenient wafer-scale substrate for the realization of high-quality nanophotonic devices. Using free-standing nanomechanical resonators embedded in on-chip Mach-Zehnder interferometers, we demonstrate efficient optomechanical transduction via gradient optical forces. Fabricated diamond resonators reproducibly show high mechanical quality factors up to 11,200. Our low cost, wideband, carrier-free photonic circuits hold promise for all-optical sensing and optomechanical signal processing at ultra-high frequencies. © 2013 Macmillan Publishers Limited. All rights reserved.


Berzak Hopkins L.F.,Lawrence Livermore National Laboratory | Meezan N.B.,Lawrence Livermore National Laboratory | Le Pape S.,Lawrence Livermore National Laboratory | Divol L.,Lawrence Livermore National Laboratory | And 67 more authors.
Physical Review Letters | Year: 2015

Recent experiments on the National Ignition Facility [M.J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] demonstrate that utilizing a near-vacuum hohlraum (low pressure gas-filled) is a viable option for high convergence cryogenic deuterium-tritium (DT) layered capsule implosions. This is made possible by using a dense ablator (high-density carbon), which shortens the drive duration needed to achieve high convergence: a measured 40% higher hohlraum efficiency than typical gas-filled hohlraums, which requires less laser energy going into the hohlraum, and an observed better symmetry control than anticipated by standard hydrodynamics simulations. The first series of near-vacuum hohlraum experiments culminated in a 6.8 ns, 1.2 MJ laser pulse driving a 2-shock, high adiabat (α∼3.5) cryogenic DT layered high density carbon capsule. This resulted in one of the best performances so far on the NIF relative to laser energy, with a measured primary neutron yield of 1.8×1015 neutrons, with 20% calculated alpha heating at convergence ∼27×. © 2015 American Physical Society.


Mackinnon A.J.,Lawrence Livermore National Laboratory | Meezan N.B.,Lawrence Livermore National Laboratory | Ross J.S.,Lawrence Livermore National Laboratory | Le Pape S.,Lawrence Livermore National Laboratory | And 66 more authors.
Physics of Plasmas | Year: 2014

High Density Carbon (HDC) is a leading candidate as an ablator material for Inertial Confinement Fusion (ICF) capsules in x-ray (indirect) drive implosions. HDC has a higher density (3.5 g/cc) than plastic (CH, 1 g/cc), which results in a thinner ablator with a larger inner radius for a given capsule scale. This leads to higher x-ray absorption and shorter laser pulses compared to equivalent CH designs. This paper will describe a series of experiments carried out to examine the feasibility of using HDC as an ablator using both gas filled hohlraums and lower density, near vacuum hohlraums. These experiments have shown that deuterium (DD) and deuterium-tritium gas filled HDC capsules driven by a hohlraum filled with 1.2 mg/cc He gas, produce neutron yields a factor of 2× higher than equivalent CH implosions, representing better than 50% Yield-over-Clean (YoC). In a near vacuum hohlraum (He = 0.03 mg/cc) with 98% laser-to-hohlraum coupling, such a DD gas-filled capsule performed near 1D expectations. A cryogenic layered implosion version was consistent with a fuel velocity = 410 ± 20 km/s with no observed ablator mixing into the hot spot. © 2014 AIP Publishing LLC.


Di Gioacchino D.,National Institute of Nuclear Physics, Italy | Marcelli A.,National Institute of Nuclear Physics, Italy | Marcelli A.,Rome International Center for Materials Science Superstripes | Puri A.,National Institute of Nuclear Physics, Italy | And 10 more authors.
ACS Applied Materials and Interfaces | Year: 2015

A simple compact temperature sensor and microheater in a wide temperature range has been developed, realizing a laser-patterned resistive structure on the surface of a synthetic polycrystalline diamond plate. Imaging and spectroscopy techniques used to investigate morphology, structure, and composition of the pattern showed that it incorporates different nondiamond carbon phases. Transport experiments revealed the semiconducting behavior of this microresistor. Thermal power measurements versus temperature are presented. A possible application of this device that may easily match compact experimental layouts avoiding both thermal anchoring offset and mechanical stress between sample and sensor is discussed. The patterned structure undergoes testing as a microthermometer, providing fast response and excellent stability versus time. It exhibits a good sensitivity that coupled to an easy calibration procedure minimizes errors and guarantees high accuracy. Plot of temperature versus input power of the resistive patterned line used as microheater shows a linear behavior in an extended temperature range. © 2015 American Chemical Society.


Huang H.,General Atomics | Carlson L.C.,General Atomics | Requieron W.,General Atomics | Rice N.,General Atomics | And 9 more authors.
Fusion Science and Technology | Year: 2016

High-density carbon (HDC) is being evaluated as an alternative to the current National Ignition Facility (NIF) point-design ablator material (glow discharge plasma, or GDP, plastic) due to its high density and optimal opacity, which leads to a higher implosion velocity. Chemical-vapor-deposition-coated HDC capsules have a near perfect surface figure but a microscopically rough surface. After polishing, the surface becomes smooth at nanometer scales but has numerous micron-sized surface pits, whose volumes, morphology, and distribution must be quantified to guide NIF target selection. Traditional metrology tools for GDP surface defects, such as the atomic force microscope (AFM) based Spheremapper and a phase-shifting differential interferometer, lack the resolution to characterize these localized features. In this paper, we describe how this metrology challenge is met by developing automated surface metrology solutions based on a high-density (HD) AFM and a Leica confocal microscope. These tools are complementary in nature. HD-AFM has a 0.1-μm spatial resolution and determines the overall shape distortion and pit statistics by tracing great circles on a capsule with high throughput. The Leica confocal microscope maps the twodimensional (2-D) surface at low magnification to find all large defects that could be missed by HD-AFM. Then, a high magnification scan inspects at a <0.3-μm lateral resolution to characterize the defect volume. These 2-D maps provide an opportunity for modeling the shell performance at the peak implosion velocity, thereby aiding capsule selection. These new and improved metrology tools provide quantitative data for the continual refinement of the NIF specifications for HDC capsules. Finally, we report on the development of a laser ablation tool that, when combined with the Leica confocal microscope, can identify, quantify, and laser-ablate GDP domes that do not meet NIF specifications.


Degenhardt M.,German Electron Synchrotron | Aprigliano G.,EMBL Hamburg | Schulte-Schrepping H.,German Electron Synchrotron | Hahn U.,German Electron Synchrotron | And 2 more authors.
Journal of Physics: Conference Series | Year: 2013

PETRA III, the most brilliant storage-ring-based synchrotron radiation source in the world, started its operation in 2009. It features 14 undulator beamlines and will be extended by further 10 beamlines in the PETRA III extension project. During the startup phase of the 14 PETRA III beamlines, fluorescence monitors based on CVD diamond screens have proven to be a very powerful tool for the monitoring of the attenuated undulator beams and for the commissioning of the optical components, e.g. slit systems and monochromators. They served as the essential instrument for the initial setup of the positron beam orbit to align the undulator photon beam along the beamline. The application of CVD diamond screens for the beam imaging at PETRA III beamlines is presented. Images taken during the beam adjustment and the beamline commissioning are shown.


Dawedeit C.,Lawrence Livermore National Laboratory | Kucheyev S.O.,Lawrence Livermore National Laboratory | Shin S.J.,Lawrence Livermore National Laboratory | Willey T.M.,Lawrence Livermore National Laboratory | And 17 more authors.
Diamond and Related Materials | Year: 2013

We report on the grain size dependent morphological, physical and chemical properties of thick microwave-plasma assisted chemical vapor deposited (MPCVD) diamond films that are used as target materials for high energy density physics experiments at the Lawrence Livermore National Laboratory. Control over the grain size, ranging from several μm to a few nm, was achieved by adjusting the CH4 content of the CH4/H2 feed gas. The effect of grain size on surface roughness, morphology, texture, density, hydrogen and graphitic carbon content was systematically studied by a variety of techniques. For depositions performed at 35 to 45 mbar and 3000 W microwave power (power density ~ 10 W cm- 3), an abrupt transition from micro-crystalline diamond to nanocrystalline diamond was observed at 3% CH 4. This transition is accompanied by a dramatic decrease in surface roughness, a six percent drop in density and an increasing content in hydrogen and graphitic carbon impurities. Guided by these results, layered nano-microhybrid diamond samples were prepared by periodically changing the growth conditions from nano- to microcrystalline. © 2013 Elsevier B.V.

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