The Swiss Center for Electronics and Microtechnology is a Swiss Research and Development company with expertise in Micro Nano Technologies, Microelectronics, Systems Engineering und Communication Technologies. The headquarters is in Neuchâtel. CSEM also has centers in the cities Muttenz, Zürich, Alpnach and Landquart in Switzerland Wikipedia.
Hakanson M.,Swiss Center for Electronics and Microtechnology |
Cukierman E.,Fox Chase Cancer Center |
Charnley M.,Swinburne University of Technology
Advanced Drug Delivery Reviews | Year: 2014
Cancer is one of the most common causes of death worldwide. Consequently, important resources are directed towards bettering treatments and outcomes. Cancer is difficult to treat due to its heterogeneity, plasticity and frequent drug resistance. New treatment strategies should strive for personalized approaches. These should target neoplastic and/or activated microenvironmental heterogeneity and plasticity without triggering resistance and spare host cells. In this review, the putative use of increasingly physiologically relevant microfabricated cell-culturing systems intended for drug development is discussed. There are two main reasons for the use of miniaturized systems. First, scaling down model size allows for high control of microenvironmental cues enabling more predictive outcomes. Second, miniaturization reduces reagent consumption, thus facilitating combinatorial approaches with little effort and enables the application of scarce materials, such as patient-derived samples. This review aims to give an overview of the state-of-the-art of such systems while predicting their application in cancer drug development. © 2013 Elsevier B.V.
News Article | August 25, 2016
« Technip signs agreement with BTG Bioliquids to design and build pyrolysis plants for biomass-to-oil production | Main | U-M study finds crop-based biofuels associated with net increase in GHGs; falsifying the assumption of inherent carbon neutrality » Using commercially available solar cells and none of the usual rare metals, researchers at the Swiss Center for Electronics and Microtechnology (CSEM) and École Polytechnique Fédérale de Lausanne (EPFL) have designed an intrinsically stable and scalable solar water splitting device that is fully based on earth-abundant materials, with a solar-to-hydrogen conversion efficiency of 14.2%. The prototype system is made up of three interconnected, new-generation, crystalline silicon solar cells attached to an electrolysis system that does not rely on rare metals. The device has already been run for more than 100 hours straight under test conditions. The method, which surpasses previous efforts in terms of stability, performance, lifespan and cost efficiency, is published in the Journal of The Electrochemical Society. crystalline Silicon (c-Si) solar cells show high solar-to-electricity efficiencies, and have demonstrated stabilities in excess of 25 years. Propelled by their attractive performance, they have continuously dominated the market since their inception, with a current worldwide market share greater than 85%. Their high production volumes have largely contributed to a price drop of 80% since 2008, currently reaching levels below $1 per watt peak. … Recently, c-Si modules have been implemented in solar-hydrogen devices, demonstrating SHE [solar-to-hydrogen efficiency] of 9.7%. As the V of the presented c-Si cells is only ∼600 mV, four cells need to be connected in series to achieve stable water splitting performance. This results in lower operating currents and limited SHE efficiencies. Alternatively, c-Si-based heterojunction (SHJ) cells can reach V values in excess of 700 mV. These VOC values are the highest ones reported for silicon wafer-based technologies, and are predominantly obtained by an excellent interface passivation with a thin (∼5 nm) film of hydrogenated intrinsic amorphous silicon (a-Si:H) between the c-Si wafer and the oppositely doped emitter, forming the p-n junction. We demonstrate in this study that, thanks to their high V , three series-connected SHJ cells can already stably drive the water splitting reaction at unprecedented SHE. In terms of performance, this is a world record for silicon solar cells and for hydrogen production without using rare metals. The key here is making the most of existing components, and using a hybrid-type of crystalline-silicon solar cell based on heterojunction technology. The researchers’ sandwich structure—using layers of crystalline silicon and amorphous silicon—allows for higher voltages needed to power directly the microstructured Ni electrocatalysts. Nearly identical performance levels were also achieved using a customized state-of-the-art proton exchange membrane (PEM) electrolyzer. The researchers used standard heterojunction cells to prove the concept; by using the best cells of that type, they would expect to achieve a performance above 16%. The research is part of the nano-tera SHINE— project to develop an efficient and cost-effective hydrogen production system using sunlight and water.
News Article | January 8, 2016
Mike Twomey: The Replacement for Vermont Yankee Was Natural Gas ISO-New England (the nonprofit independent entity that ensures the reliability of the electric grid in New England) publishes data that shows daily generation by fuel type. That data shows that in 2014 (the last year of Vermont Yankee's operation), natural-gas-fired generators supplied 43.1% of the energy in New England, while nuclear provided 34%. In 2015 (the first year since 1972 without Vermont Yankee), natural-gas-fired generators supplied 48.6% of the energy in New England, while nuclear provided 29.5%. The bottom line is that without Vermont Yankee, nuclear's carbon-free contribution to the New England electric grid fell by 5.3 million megawatt-hours in 2015 compared to 2014. Panasonic Corp. President Kazuhiro Tsuga said the company will spend up to $1.6 billion on an advanced battery factory with electric-car maker Tesla Motors Inc., an investment it hopes to cement its future in automotive electronics. The Japanese consumer electronics giant and Tesla are jointly funding an up to $5 billion battery plant in Nevada. Panasonic hasn’t previously disclosed the full size of its investment. It will be several years before that factory is humming at full steam, and for Panasonic, the wait will be costly because its lithium-ion battery business has struggled to make money. BBC: Is Sweden's 'Green Miracle' a Model for the Rest of the World? Despite the enviable safety track record, and the fact that it provides 40% of the country's electricity, nuclear power is now on the defensive in Sweden. The government wants to replace it, in the long term, with what they say are greener sources. However, some experts say that nuclear has been the critical factor in the country's ability to grow the economy while cutting carbon. "In the start of the 1970s, we started putting nuclear power plants on-line, and what we saw was that the economy kept growing but the emissions started falling very rapidly," said Dr. Staffan Qvist from Uppsala University, who researches nuclear issues. Scientists at the Energy Department's National Renewable Energy Laboratory (NREL) and at the Swiss Center for Electronics and Microtechnology (CSEM) have jointly set a new world record for converting non-concentrated (1-sun) sunlight into electricity using a dual-junction III-V/Si solar cell. The newly certified record conversion efficiency of 29.8 percent was set using a top cell made of gallium indium phosphide developed by NREL, and a bottom cell made of crystalline silicon developed by CSEM using silicon heterojunction technology. The two cells were made separately and then stacked by NREL. The record was published in 'Solar cell efficiency tables.' Climate change could lead to significant declines in electricity production in coming decades as water resources are disrupted, said a study published on Monday. Hydropower stations and thermoelectric plants, which depend on water to generate energy, together contribute about 98 percent of the world's electricity production, said the study published in the journal Nature Climate Change.
Portuondo-Campa E.,Swiss Center for Electronics and Microtechnology |
Paschotta R.,RP Photonics Consulting GmbH |
Lecomte S.,Swiss Center for Electronics and Microtechnology
Optics Letters | Year: 2013
We report on the ultralow timing jitter of the 100 MHz pulse trains generated by two identical passively modelocked diode-pumped solid-state lasers (DPSSLs) emitting at 1556 nm. Ultralow timing jitter of 83 as (integrated from 10 kHz to 50 MHz) for one laser has been measured with a balanced optical cross-correlator as timing discriminator. Extremely low intensity noise has been measured as well. Several measurement techniques have been used and show similar jitter results. Different possible noise sources have been theoretically investigated and compared to the measured jitter power spectral density. It is found that although the measured integrated jitter is quite low, it is still significantly above the quantum limit in the considered frequency span. Therefore, there is a substantial potential for technical improvements that could make passively mode-locked DPSSL outperform fiber lasers as source of microwaves with low phase noise. © 2013 Optical Society of America.
Ali K.,Ecole Polytechnique Federale de Lausanne |
Fleuret F.,Idiap Research Institute |
Hasler D.,Swiss Center for Electronics and Microtechnology |
Fua P.,Ecole Polytechnique Federale de Lausanne
IEEE Transactions on Pattern Analysis and Machine Intelligence | Year: 2012
We propose a new learning strategy for object detection. The proposed scheme forgoes the need to train a collection of detectors dedicated to homogeneous families of poses, and instead learns a single classifier that has the inherent ability to deform based on the signal of interest. We train a detector with a standard AdaBoost procedure by using combinations of pose-indexed features and pose estimators. This allows the learning process to select and combine various estimates of the pose with features able to compensate for variations in pose without the need to label data for training or explore the pose space in testing. We validate our framework on three types of data: hand video sequences, aerial images of cars, and face images. We compare our method to a standard boosting framework, with access to the same ground truth, and show a reduction in the false alarm rate of up to an order of magnitude. Where possible, we compare our method to the state of the art, which requires pose annotations of the training data, and demonstrate comparable performance. © 2012 IEEE.
Ranieri J.,Ecole Polytechnique Federale de Lausanne |
Chebira A.,Swiss Center for Electronics and Microtechnology |
Vetterli M.,Ecole Polytechnique Federale de Lausanne
IEEE Transactions on Signal Processing | Year: 2014
A classic problem is the estimation of a set of parameters from measurements collected by only a few sensors. The number of sensors is often limited by physical or economical constraints and their placement is of fundamental importance to obtain accurate estimates. Unfortunately, the selection of the optimal sensor locations is intrinsically combinatorial and the available approximation algorithms are not guaranteed to generate good solutions in all cases of interest. We propose FrameSense, a greedy algorithm for the selection of optimal sensor locations. The core cost function of the algorithm is the frame potential, a scalar property of matrices that measures the orthogonality of its rows. Notably, FrameSense is the first algorithm that is near-optimal in terms of mean square error, meaning that its solution is always guaranteed to be close to the optimal one. Moreover, we show with an extensive set of numerical experiments that FrameSense achieves state-of-the-art performance while having the lowest computational cost, when compared to other greedy methods. © 2014 IEEE.
Gallinet B.,Swiss Center for Electronics and Microtechnology |
Gallinet B.,Ecole Polytechnique Federale de Lausanne |
Martin O.J.F.,Ecole Polytechnique Federale de Lausanne
ACS Nano | Year: 2013
Plasmonic modes with long radiative lifetimes, subradiant modes, combine strong confinement of the electromagnetic energy at the nanoscale with a steep spectral dispersion, which makes them promising for biochemical sensors or immunoassays. Subradiant modes have three decay channels: Ohmic losses, their extrinsic coupling to radiation, and possibly their intrinsic dipole moment. In this work, the performance of subradiant modes for refractive index sensing is studied with a general analytical and numerical approach. We introduce a model for the impact that has different decay channels of subradiant modes on the spectral resolution and contrast. It is shown analytically and verified numerically that there exists an optimal value of the mode coupling for which the spectral dispersion of the resonance line shape is maximal. The intrinsic width of subradiant modes determines the value of the dispersion maximum and depends on the penetration of the electric field in the metallic nanostructure. A figure of merit, given by the ratio of the sensitivity to the intrinsic width, which are both intrinsic properties of subradiant modes, is introduced. This figure of merit can be directly calculated from the line shape in the far-field optical spectrum and accounts for the fact that both the spectral resolution and contrast determine the limit of detection. An expression for the intrinsic width of a plasmonic mode is derived and calculated from the line shape parameters and using perturbation theory. The method of analysis introduced in this work is illustrated for dolmen and heptamer nanostructures. Fano-resonant systems have the potential to act as very efficient refractive index sensing platforms compared to Lorentz-resonant systems, due to control of their radiative losses. This study paves the way toward sensitive nanoscale biochemical sensors and immunoassays with a low limit of detection and, in general, any nano-optical device where Ohmic losses limit the performance. © 2013 American Chemical Society.
Guillaumee M.,Swiss Center for Electronics and Microtechnology
Optics express | Year: 2011
An analytical model based on a modal expansion method is developed to investigate the optical transmission through metal gratings. This model gives analytical expressions for the transmission as well as for the dispersion relations of the modes responsible for high transmission. These expressions are accurate even for real metals used in the visible - near-infrared wavelength range, where surface plasmon polaritons (SPP's) are excited. The dispersion relations allow the nature of the modes to be assessed. We find that the transmission modes are hybrid between Fabry-Pérot like modes and SPP's. It is also shown that it is important to consider different refractive indices above and below the gratings in order to determine the nature of the hybrid modes. These findings are important as they clarify the nature of the modes responsible for high transmission. It can also be useful as a design tool for metal gratings for various applications.
News Article | November 29, 2016
Solar planes have already traversed the Alps and flown around the world, but one team has its sights set a little higher: the edge of space. SolarStratos is planning to fly a solar-powered plane to an altitude of over 80,000 ft (24,000 m), from where the curvature of the Earth as well as daytime stars will be visible. The aim of the project is to demonstrate the potential of renewable energy and to explore the possibility of flying people to such altitudes using solar technology. Although it began in 2014, it has hit a significant milestone this month with the completion of the hangar that will serve as the team's operational base, in which the SolarStratos plane will be developed and maintained and from where testing will be carried out. The plane has been built by electric- and solar-aircraft firm PC-Aero, which was behind the Elektra One plane, and its solar systems have been developed by the Swiss Center for Electronics and Microtechnology. It is said to be the first commercial two-seater solar plane in history and the first that will reach the stratosphere. It measures 8.5-m (27.9-ft) long, has a wingspan of 24.9 m (81.7 ft) and weighs in at just 450 kg (992 lb). There are 22 sq m (237 sq ft) of solar panels covering the plane that power a 32-kW electric engine and charge a 20-kWh lithium-ion battery. These will apparently allow the plane to stay airborne for over 24 hours, although its inaugural flight is slated to be a little shorter, clocking in at five hours – two to ascend, 15 minutes to look around, and three hours to descend. To save weight during the flight, the plane will not be pressurized. Instead, pilot Raphaël Domjan will wear a pressurized suit, like those worn by astronauts. As the suit will be connected to and powered by the plane, it will not allow him, should the need arise, to eject or to use a parachute. Among the factors at play will be temperatures as low as 70 °C (-94 °F) and atmospheric pressure of around 5 percent that on Earth. Domjan apparently had the idea for the SolarStratos project during the Atlantic crossing of his PlanetSolar boat's round-the-world journey. The hangar and the plane are due to be publicly launched on December 7th, with test flights scheduled to begin early next year. The mission itself is currently set for 2018. The exceptionally well-done video below provides an idea of what the journey will be like.
News Article | January 13, 2016
A new world efficiency record for the conversion of non-concentrated sunlight into electricity via dual-junction III-V/Si solar cells has been achieved by researchers at the National Renewable Energy Laboratory (NREL) and the Swiss Center for Electronics and Microtechnology (CSEM), according to a new press release. The new world record — an efficiency of 29.8% — was achieved via the use of a top layer/cell composed of gallium indium phosphide (courtesy NREL) and a bottom layer/cell composed of crystalline silicon (courtesy CSEM), incorporated using silicon heterojunction technology. “It’s a record within this mechanically stacked category,” stated David Young, a senior researcher at NREL. “The performance of the dual-junction device exceeded the theoretical limit of 29.4% for crystalline silicon solar cells.” “We believe that the silicon heterojunction technology is today the most efficient silicon technology for application in tandem solar cells,” stated Christophe Ballif, head of PV activities at CSEM. “CSEM partnered with the NREL scientists with the objective to demonstrate that 30% efficient tandem cells can be realized using silicon heterojunction bottom cells, thanks to the combination with high performance top cells such as those developed by NREL,” noted Matthieu Despeisse, the manager of crystalline silicon activities at CSEM. The researchers involved in the work think that the new approach can be improved to allow for even greater conversion efficiencies than that of the new record. Get CleanTechnica’s 1st (completely free) electric car report → “Electric Cars: What Early Adopters & First Followers Want.” Come attend CleanTechnica’s 1st “Cleantech Revolution Tour” event → in Berlin, Germany, April 9–10. Keep up to date with all the hottest cleantech news by subscribing to our (free) cleantech newsletter, or keep an eye on sector-specific news by getting our (also free) solar energy newsletter, electric vehicle newsletter, or wind energy newsletter.