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Fuveau, France

Misevic G.N.,Gimmune GmbH | Benassayag G.,French National Center for Scientific Research | Rasser B.,Orsay Physics | Sales P.,French National Center for Scientific Research | And 3 more authors.
Journal of Molecular Structure | Year: 2014

Single cell 'omics' requires a technological platform with reliable and high throughput single cell analyses with single molecular detection and quantification. Presently available options are to either to detect many different macromolecules and metabolites extracted from many cells, thus obtaining partial 'omics' of an average cell or to study only few single cells and be limited to semi-quantitative analyses and detection of a few abundant molecules. Here we present a new design and prototype proof of concept construction of high throughput nano-electrophoretic separation (NEA) device and nano in micro array (NiMA) affinity probe device for a complete single cell 'omics' single bio-molecule polymers detection and quantification analyses. Prototype devices were constructed using gallium ion Focus Ion Beam (FIB), Gas Injection System (GIS) and Scanning Electron Microscope (SEM) crossbeam instruments. The NEA device accommodates 100 different cell samplings per 1 cm2 chip with arrays of open nano-electrophoretic guides. The NiMA bio-sensor device on 1 cm2 can accommodate 2500 cells in a micro-well array which consists of 250,000 probe markers in nano-well array located in each micro-well. Using Secondary Ion Mass Spectrometry (SIMS) we have demonstrated the direct detection of a single protein molecule and proved the feasibility of single bio-molecular detection and quantification concept for NEA and NIMA. Our concept validates high throughput and complete and quantitative single cell 'omics' with single molecular detection analyses without labeling. Thus, it is superior to commonly used microfluidics, capillary electrophoresis and micro-arrays using mass spectrometry and fluorescent labeling for molecular detection. © 2014 Elsevier B.V. All rights reserved.

Porfido N.,University of Pisa | Porfido N.,ASML Inc | Bezuglov N.N.,Saint Petersburg State University | Bruvelis M.,University of Latvia | And 23 more authors.
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015

By photoionizing hyperfine (HF) levels of the Cs state 62P3/2 in a slow and cold atom beam, we find how their population depends on the excitation laser power. The long time (around 180μs) spent by the slow atoms inside the resonant laser beam is large enough to enable exploration of a unique atom-light interaction regime heavily affected by time-dependent optical pumping. We demonstrate that, under such conditions, the onset of nonlinear effects in the population dynamics and optical pumping occurs at excitation laser intensities much smaller than the conventional respective saturation values. The evolution of population within the HF structure is calculated by numerical integration of the multilevel optical Bloch equations. The agreement between numerical results and experiment outcomes is excellent. All main features in the experimental findings are explained by the occurrence of "dark" and "bright" resonances leading to power-dependent branching coefficients. © 2015 American Physical Society.

Berbezier I.,CNRS Institute Materials Microelectronics nanosciences of Provence | Aouassa M.,CNRS Institute Materials Microelectronics nanosciences of Provence | Ronda A.,CNRS Institute Materials Microelectronics nanosciences of Provence | Favre L.,CNRS Institute Materials Microelectronics nanosciences of Provence | And 4 more authors.
Journal of Applied Physics | Year: 2013

We develop self-organisation processes for the fabrication of 2D arrays of Si and Ge quantum dots. The processes make use of the dewetting phenomenon which involves the transformation of a 2D thin film into an array of isolated 3D islands through a morphological instability. We show that self-organization of monodisperse ultra-small nanocrystals (NCs) into large scale patterns with ad hoc features can be created via heterogeneous dewetting. The process involves dewetting of thin films nanopatterned by electron beam lithography (EBL) or liquid metal alloy source focused ion beam (LMAIS-FIB). Heterogeneous dewetting is initiated at the edges of the patterns. It provokes the retraction of the thin film following the kinetics of surface diffusion and ends by the formation of faceted monocrystalline NCs regularly positioned. Their geometrical features and lateral arrangements can be tuned by changing the pitch, size, and shape of the patterns. The process developed in this study is adapted to the fabrication of NCs based floating gate memories. © 2013 American Institute of Physics.

Marcus I.C.,CSIC - Institute of Materials Science | Marcus I.C.,Aix - Marseille University | Berbezier I.,Aix - Marseille University | Ronda A.,Aix - Marseille University | And 8 more authors.
Crystal Growth and Design | Year: 2011

We report a novel method for obtaining ordered arrays of self-assembled Ge nanowires (NWs) using Au seed catalysts, with the latter deposited using a focused ion beam (FIB). For this purpose we apply a three-step process involving first FIB nanopatterning, a second step of AuSi seed formation during UHV annealing, and third the nucleation and growth of Ge NWs by combining molecular-beam epitaxy (MBE) and the vapor-liquid-solid (VLS) process. We show that FIB allows for the local implantation of Au in the areas impacted by the ion beam; the implanted Au evolves during annealing into AuSi clusters, serving as nucleation seeds for the nucleation and growth of Ge NWs. We thus prove that FIB with gold ions is a successful method to obtain gold-catalyzed self-assembled nanowires. We obtain Ge NWs of homogeneous dimensions and oriented in-plane along [110] directions, as a consequence of a strain-driven process. Wire kinking is governed by surface morphological features. Based on our experimental results, we elaborate on the general mechanisms of MBE growth of quantum wires under epitaxial strain, which we exemplify for Ge NWs on Si(001) but hold for many other lattice-mismatched semiconductor material combinations. © 2011 American Chemical Society.

Kime L.,University Paris - Sud | Fioretti A.,University Paris - Sud | Fioretti A.,University of Pisa | Fioretti A.,National Research Council Italy | And 11 more authors.
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

We propose a source for high-brightness ion and electron beams based on the ionization of an effusive atomic beam which is transversely laser cooled and compressed. The very low transverse temperature (mK range) and the relative low density of the starting atomic sample ensure excellent initial conditions for obtaining bright and monochromatic charge sources. In contrast to the standard photoionization techniques used by similar sources, we utilize field ionization of Rydberg atoms. This approach allows a substantial reduction of the required laser power and copes differently with the problems of the energy spread created during the ionization process and of the stochastic space-charge effect. Theoretical modeling and prospective ideas of this emerging technology are given. © 2013 American Physical Society.

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