Results for "P. Courtois"

total 125871took 0.12s
High-performance electronic cooling with superconducting tunnel junctionsAug 23 2016When biased at a voltage just below a superconductor's energy gap, a tunnel junction between this superconductor and a normal metal cools the latter. While the study of such devices has long been focussed to structures of submicron size and consequently ... More
Andreev Reflection and Proximity effectDec 02 1999Dec 23 1999The Andreev Reflection is the key mechanism for the superconducting proximity effect. It provides phase correlations in a system of non-interacting electrons at mesoscopic scales, i.e. over distances much larger than the microscopic lengths : Fermi wavelength ... More
Trapping hot quasi-particles in a high-power superconducting electronic coolerApr 06 2013Jun 23 2013The performance of hybrid superconducting electronic coolers is usually limited by the accumulation of hot quasi-particles in the superconducting leads. This issue is all the more stringent in large-scale and high-power devices, as required by applications. ... More
Probing oppositely charged surfactant and copolymer interactions by isothermal titration microcalorimetryJul 26 2011The complexation between charged-neutral block copolymers and oppositely charged surfactants was investigated by light scattering experiments and by isothermal titration calorimetry (ITC). The copolymer was poly(sodium acrylate)-b-poly(acrylamide) and ... More
Constructive Non-Linear Polynomial Cryptanalysis of a Historical Block CipherFeb 07 2019One of the major open problems in symmetric cryptanalysis is to discover new specif i c types of invariant properties which can hold for a larger number of rounds of a block cipher. We have Generalised Linear Cryptanalysis (GLC) and Partitioning Cryptanalysis ... More
Atom cooling and trapping by disorderMay 29 1998We demonstrate the possibility of three-dimensional cooling of neutral atoms by illuminating them with two counterpropagating laser beams of mutually orthogonal linear polarization, where one of the lasers is a speckle field, i.e. a highly disordered ... More
Coherent low-energy charge transport in a diffusive S-N-S junctionJul 10 2001Oct 29 2001We have studied the current voltage characteristics of diffusive mesoscopic Nb-Cu-Nb Josephson junctions with highly-transparent Nb-Cu interfaces. We consider the low-voltage and high-temperature regime eV<\epsilon_{c}<k_{B}T where epsilon_{c} is the ... More
Sub-50 mK electronic cooling with large-area superconducting tunnel junctionsFeb 24 2014Nov 06 2014In electronic cooling with superconducting tunnel junctions, the cooling power is counterbalanced by the interaction with phonons and by the heat flow from the overheated leads. We study aluminium-based coolers that are equipped with a suspended normal ... More
Calorimetric readout of a superconducting proximity-effect thermometerJan 08 2009A proximity-effect thermometer measures the temperature dependent critical supercurrent in a long superconductor - normal metal - superconductor (SNS) Josephson junction. Typically, the transition from the superconducting to the normal state is detected ... More
Origin of Hysteresis in a Proximity Josephson JunctionMay 29 2008Aug 25 2008We investigate hysteresis in the transport properties of Superconductor - Normal metal - Superconductor (S-N-S) junctions at low temperatures by measuring directly the electron temperature in the normal metal. Our results demonstrate unambiguously that ... More
Calibration of the Faber-Jackson relation for M31 globular clusters using Hipparcos dataOct 14 1998In this paper we present a data analysis regarding globular clusters as possible extragalactic distance indicators. For this purpose, we collected all velocity dispersion measurements published for galactic and M31 globular clusters. The slope and the ... More
The spectral conductance of a proximity superconductor and the re-entrance effectFeb 01 1999Aug 18 1999In a mesoscopic metal in proximity with a superconductor, the electronic conductance is enhanced in a very energy-sensitive way. In this paper, we discuss the spectral conductance of a proximity superconductor from both the theoretical and experimental ... More
Characterisation of the Etching Quality in Micro-Electro-Mechanical Systems by Thermal Transient MethodologyNov 21 2007Our paper presents a non-destructive thermal transient measurement method that is able to reveal differences even in the micron size range of MEMS structures. Devices of the same design can have differences in their sacrificial layers as consequence of ... More
Noise Correlations in Three-Terminal Diffusive Superconductor-Normal Metal-Superconductor NanostructuresApr 21 2011Aug 18 2011We present measurements of current noise and cross-correlations in three-terminal Superconductor-Normal metal-Superconductor (S-N-S) nanostructures that are potential solid-state entanglers thanks to Andreev reflections at the N-S interfaces. The noise ... More
A New General-Purpose Method to Multiply 3x3 Matrices Using Only 23 MultiplicationsAug 14 2011Aug 19 2011One of the most famous conjectures in computer algebra is that matrix multiplication might be feasible in not much more than quadratic time. The best known exponent is 2.376, due to Coppersmith and Winograd. Many attempts to solve this problems in the ... More
The Josephson critical current in a long mesoscopic S-N-S junctionAug 09 2000Feb 07 2001We carry out an extensive experimental and theoretical study of the Josephson effect in S-N-S junctions made of a diffusive normal metal (N) embedded between two superconducting electrodes (S). Our experiments are performed on Nb-Cu-Nb junctions with ... More
A project of advanced solid-state neutron polarizer for PF1B instrument at ILLJun 11 2019Among Super-Mirror (SM) polarizers, solid-state devices have many advantages. The most relevant is 5-10 times smaller length compared to air-gap polarizers allowing to apply stronger magnetic fields. An important condition for a good SM polarizer is the ... More
Advanced broad-band solid-state supermirror polarizers for cold neutronsJun 06 2016Jun 15 2016An ideal solid-state supermirror (SM) neutron polarizer assumes total reflection of neutrons from the SM coating for one spin-component and total absorption for the other, thus providing a perfectly polarized neutron beam at the exit. However, in practice, ... More
Resistive transport in a mesoscopic proximity superconductorSep 19 1996We review transport measurements in a normal metal (N) in contact with one or two superconducting (S) islands. From the experiment, we distinguish the Josephson coupling, the mesoscopic fluctuations and the proximity effect. In a loop-shaped N conductor, ... More
Re-entrance of the metallic conductance in a mesoscopic proximity superconductorMay 03 1996Sep 30 1996We present an experimental study of the diffusive transport in a normal metal near a superconducting interface, showing the re-entrance of the metallic conductance at very low temperature. This new mesoscopic regime comes in when the thermal coherence ... More
Joule overheating poisons the fractional ac Josephson effect in topological Josephson junctionsMar 20 2018Oct 22 2018Topological Josephson junctions designed on the surface of a 3D-topological insulator (TI) harbor Majorana bound states (MBS's) among a continuum of conventional Andreev bound states. The distinct feature of these MBS's lies in the $4\pi$-periodicity ... More
Extragalactic Cepheid databaseApr 02 1999Jun 29 1999We present in this paper an exhaustive compilation of all published data of extragalactic Cepheids. We have checked every light curve in order to characterize the different types of Cepheid and detect potential overtone pulsators, or to estimate the quality ... More
Electron and phonon Cooling in a Superconductor - Normal Metal - Superconductor Tunnel JunctionDec 01 2006May 08 2007We present evidence for the cooling of normal metal phonons by electron tunneling in a Superconductor - Normal metal - Superconductor tunnel junction. The normal metal electron temperature is extracted by comparing the device current-voltage characteristics ... More
Study of the optimal conditions for NV- center formation in type 1b diamond, using photoluminescence and positron annihilation spectroscopiesApr 30 2011Aug 24 2011We studied the parameters to optimize the production of negatively-charged nitrogen-vacancy color centers (NV-) in type~1b single crystal diamond using proton irradiation followed by thermal annealing under vacuum. Several samples were treated under different ... More
First DENIS I-band extragalactic catalogJan 29 1999This paper presents the first I-band photometric catalog of the brightest galaxies extracted from the Deep Near Infrared Survey of the Southern Sky (DENIS) An automatic galaxy recognition program has been developed to build this provisional catalog. The ... More
On The Longest Chain Rule and Programmed Self-Destruction of Crypto CurrenciesMay 02 2014Dec 10 2014In this paper we revisit some major orthodoxies which lie at the heart of the bitcoin crypto currency and its numerous clones. In particular we look at The Longest Chain Rule, the monetary supply policies and the exact mechanisms which implement them. ... More
A dynamics-free lower bound on the mass of our galaxyNov 14 2016We use a sample of Milky Way (MW) analogs for which we have stellar and disk gas mass measurements, published measurements of halo gas masses of the MW and of similar galaxies, and the well-established value of the cosmological baryon fraction to place ... More
Star Formation in Nearby Isolated GalaxiesJul 19 2013Jul 22 2013We use the FUV fluxes measured with the GALEX to study the star formation properties of galaxies collected in the "Local Orphan Galaxies" catalog (LOG). Among 517 LOG galaxies having radial velocities V(LG) < 3500 km/s and Galactic latitudes |b|> 15 degr, ... More
Cosmicflows-3: Cosmography of the Local VoidMay 20 2019Cosmicflows-3 distances and inferred peculiar velocities of galaxies have permitted the reconstruction of the structure of over and under densities within the volume extending to 0.05c. This study focuses on the under dense regions, particularly the Local ... More
Cosmicflows-3: Cold Spot Repeller?Aug 24 2017The three-dimensional gravitational velocity field within z~0.1 has been modeled with the Wiener filter methodology applied to the Cosmicflows-3 compilation of galaxy distances. The dominant features are a basin of attraction and two basins of repulsion. ... More
Etching suspended superconducting hybrid junctions from a multilayerNov 15 2011Jun 23 2012A novel method to fabricate large-area superconducting hybrid tunnel junctions with a suspended central normal metal part is presented. The samples are fabricated by combining photo-lithography and chemical etch of a superconductor - insulator - normal ... More
Laue Lens Development for Hard X-rays (>60 keV)Nov 16 2005Results of reflectivity measurements of mosaic crystal samples of Cu (111) are reported. These tests were performed in the context of a feasibility study of a hard X-ray focusing telescope for space astronomy with energy passband from 60 to 600 keV. The ... More
Direct measurement of the Seebeck coefficient in a Kondo-correlated single-quantum-dot transistorNov 10 2018We report on the first measurement of the Seebeck coefficient in a tunnel-contacted and gate-tunable individual single-quantum dot junction in the Kondo regime, fabricated using the electromigration technique. This fundamental thermoelectric parameter ... More
Non-Linear Thermovoltage in a Single-Electron TransistorDec 16 2018We perform direct thermovoltage measurements in a single-electron transistor, using on-chip local thermometers, both in the linear and non-linear regimes. Using a model which accounts for co-tunneling, we find excellent agreement with the experimental ... More
Single Quantum Level Electron TurnstileJan 11 2016We report on the realization of a single-electron source, where current is transported through a single-level quantum dot (Q), tunnel-coupled to two superconducting leads (S). When driven with an ac gate voltage, the experiment demonstrates electron turnstile ... More
Isospectral finiteness on convex cocompact hyperbolic 3-manifoldsDec 14 2016Jan 06 2017In this paper we show that a given set of lengths of closed geodesics, there are only finitely many convex cocompact hyperbolic 3-manifolds with that specified length spectrum, homotopy equivalent to a given 3-manifold without a handlebody factor, up ... More
Global Attenuation in Spiral Galaxies in Optical and Infrared BandsSep 04 2019The emerging light from a galaxy is under the influence of its own interstellar medium, as well as its spatial orientation. Considering a sample of 2,239 local spiral galaxies in optical (SDSS u, g, r, i, and z) and infrared bands (WISE W1, W1), we study ... More
Soft gamma-ray optics: new Laue lens design and performance estimatesOct 02 2009Laue lenses are an emerging technology based on diffraction in crystals that allows the concentration of soft gamma rays. This kind of optics that works in the 100 keV - 1.5 MeV band can be used to realize an high-sensitivity and high-angular resolution ... More
On Subversive Miner Strategies and Block Withholding Attack in Bitcoin Digital CurrencyJan 28 2014Dec 02 2014Bitcoin is a "crypto currency", a decentralized electronic payment scheme based on cryptography. Bitcoin economy grows at an incredibly fast rate and is now worth some 10 billions of dollars. Bitcoin mining is an activity which consists of creating (minting) ... More
The quasi-linear nearby UniverseJul 10 2018The local Universe provides a unique opportunity for testing cosmology and theories of structure formation. To facilitate this opportunity we present a new method for the reconstruction of the quasi-linear matter density and velocity fields from galaxy ... More
Ultracold-neutron infrastructure for the gravitational spectrometer GRANITNov 11 2008Jan 29 2009The gravitational spectrometer GRANIT will be set up at the Institut Laue Langevin. It will profit from the high ultracold neutron density produced by a dedicated source. A monochromator made of crystals from graphite intercalated with potassium will ... More
Feasibility study of a Laue lens for hard X-rays for space astronomyNov 19 2004Jan 05 2011We report on the feasibility study of a Laue lens for hard X-rays (>60 keV)based on mosaic crystals, for astrophysical applications. In particular we discuss the scientific motivations, its functioning principle, the procedure followed to select the suitable ... More
Recoil and momentum diffusion of an atom close to a vacuum-dielectric interfaceApr 09 1998We derive the quantum-mechanical master equation (generalized optical Bloch equation) for an atom in the vicinity of a flat dielectric surface. This equation gives access to the semiclassical radiation pressure force and the atomic momentum diffusion ... More
Lack of Unique Factorization as a Tool in Block Cipher CryptanalysisMay 12 2019Linear (or differential) cryptanalysis may seem dull topics for a mathematician: they are about super simple invariants characterized by say a word on n=64 bits with very few bits at 1, the space of possible attacks is small, and basic principles are ... More
Subkelvin tunneling spectroscopy showing Bardeen-Cooper-Schrieffer superconductivity in heavily boron-doped silicon epilayersJul 21 2010Nov 06 2012Scanning tunneling spectroscopies in the subKelvin temperature range were performed on superconducting Silicon epilayers doped with Boron in the atomic percent range. The resulting local differential conductance behaved as expected for a homogeneous superconductor, ... More
Thermal Conductance of a Single-Electron TransistorApr 09 2017We report on combined measurements of heat and charge transport through a single-electron transistor. The device acts as a heat switch actuated by the voltage applied on the gate. The Wiedemann-Franz law for the ratio of heat and charge conductances is ... More
A Framework for Computing Transport Properties of Carbon Nanotube-based Conductance Biochemical SensorsAug 14 2007In this paper we present a framework for fast quantum conductance calculations of carbon nanotube-based sensing devices targeting aromatic amino acids within a tight binding approximation. The method begins by a novel parameterization procedure based ... More
Atomic diffraction by a thin phase gratingAug 25 2004We present a semiclassical perturbation method for the description of atomic diffraction by a weakly modulated potential. It proceeds in a way similar to the treatment of light diffraction by a thin phase grating, and consists in calculating the atomic ... More
Update on HI data collection from GBT, Parkes and Arecibo telescopes for the Cosmic Flows projectNov 20 2014Cosmic Flows is an international multi-element project with the goal to map motions of galaxies in the Local Universe. Kinematic information from observations in the radio HI line and photometry at optical or near-infrared bands are acquired to derive ... More
Cosmicflows-2: SNIa Calibration and H0Feb 17 2012The construction of the Cosmicflows-2 compendium of distances involves the merging of distance measures contributed by the following methods: (Cepheid) Period-Luminosity, Tip of the Red Giant Branch (TRGB), Surface Brightness Fluctuation (SBF), Luminosity-Linewidth ... More
The Evolution of Embedding Metadata in Blockchain TransactionsJun 18 2018The use of blockchains is growing every day, and their utility has greatly expanded from sending and receiving crypto-coins to smart-contracts and decentralized autonomous organizations. Modern blockchains underpin a variety of applications: from designing ... More
Local spectroscopy of a proximity superconductor at very low temperatureJun 15 2001We performed the local spectroscopy of a Normal-metal--Superconductor (N-S) junction with the help of a very low temperature (60 mK) Scanning Tunneling Microscope (STM). The spatial dependence of the local density of states was probed locally in the vicinity ... More
Digital planetariums as virtual museums for discovering today's scienceNov 12 2013Our study's concern is about how to enlarge the scope of the virtual museum concept from the mediation activities as they are carried out in today's digital planetariums to training activities dedicated to the public. We assume that these educational ... More
R&D progress on second-generation crystals for Laue lens applicationsAug 06 2008The concept of a gamma-ray telescope based on a Laue lens offers the possibility to increase the sensitivity by more than an order of magnitude with respect to existing instruments. Laue lenses have been developed by our collaboration for several years ... More
Cosmic Flows surveys and CLUES simulationsMay 21 2012Cosmic Flows is a program to determine galaxy distances for 30,000 galaxies with systematic errors below 2%, almost ten times the number currently known and a five-fold improvement in systematics. The resultant velocity field will provide input for constrained ... More
Uniform growth of groups acting on Cartan-Hadamard spacesOct 17 2008Let $X$ be an $n$-dimensional simply connected manifold of pinched sectional curvature $-a^2 \leq K \leq -1$. There exist a positive constant $C(n,a)$ such that for any finitely generated discrete group $\Gamma$ acting on $X$, then either $\Gamma$ is ... More
Visualization of structures and cosmic flows in the Local UniverseNov 13 2012A visualization of three-dimensional structures and cosmic flows is presented using information from the Extragalactic Distance Database V8k redshift catalog and peculiar velocities from the Cosmicflows-1 survey. Structures within a volume bounded at ... More
Poincaré inequality on complete Riemannian manifolds with Ricci curvature bounded belowJan 12 2018We prove that complete Riemannian manifolds with polynomial growth and Ricci curvature bounded from below, admit uniform Poincar\'e inequalities. A global, uniform Poincar\'e inequality for horospheres in the universal cover of a closed, $n$-dimensional ... More
Distributed Ledger Privacy: Ring Signatures, Möbius and CryptoNoteFeb 07 2019Distributed ledger and blockchain systems are expected to make financial systems easier to audit, reduce counter-party risk and transfer assets seamlessly. The key concept is a token controlled by a cryptographic private key for spending, and represented ... More
Cosmicflows-2: I-band Luminosity - HI Linewidth CalibrationFeb 15 2012In order to measure distances with minimal systematics using the correlation between galaxy luminosities and rotation rates it is necessary to adhere to a strict and tested recipe. We now derive a measure of rotation from a new characterization of the ... More
The Unreasonable Fundamental Incertitudes Behind Bitcoin MiningOct 29 2013Apr 10 2014Bitcoin is a "crypto currency", a decentralized electronic payment scheme based on cryptography which has recently gained excessive popularity. Scientific research on bitcoin is less abundant. A paper at Financial Cryptography 2012 conference explains ... More
An estimation of the Local growth rate from Cosmicflows-3 peculiar velocitiesJan 11 2019Mar 19 2019This article explores three usual estimators, noted as $v_{12}$ of the pairwise velocity, $\psi_1$ and $\psi_2$ of the observed two-point galaxy peculiar velocity correlation functions. These estimators are tested on mock samples of {\it Cosmicflows-3} ... More
A very low temperature STM for the local spectroscopy of mesoscopic structuresJul 07 2000Jan 30 2001We present the design and operation of a very-low temperature Scanning Tunneling Microscope (STM) working at $60 mK$ in a dilution refrigerator. The STM features both atomic resolution and micron-sized scanning range at low temperature. This work is the ... More
Quasiparticle diffusion based heating in superconductor tunneling micro-coolersOct 10 2008Sep 13 2009In a hybrid Superconductor - Insulator - Normal metal tunnel junction biased just below the gap, the extraction of hot electrons out of the normal metal results in electronic cooling effect. The quasiparticles injected in the superconductor accumulate ... More
Rigidity of amalgamated product in negative curvatureJun 17 2005Let $\Gamma$ be the fundamental group of a compact n-dimensional riemannian manifold X of sectional curvature bounded above by -1. We suppose that $\Gamma$ is a free product of its subgroup A and B over the amalgamated subgroup C. We prove that the critical ... More
Combined scanning force microscopy and scanning tunneling spectroscopy of an electronic nano-circuit at very low temperatureOct 16 2006Mar 28 2007We demonstrate the combination of scanning force microscopy and scanning tunneling spectroscopy in a local probe microscope operating at very low temperature (60 mK). This local probe uses a quartz tuning fork ensuring high tunnel junction stability. ... More
Closed, negatively curved Riemannian manifolds with a flat horosphere are hyperbolicJan 24 2017Feb 03 2017We prove that the existence of one flat horosphere in the universal cover of a closed, strictly quarter pinched, negatively curved Riemannian manifold of dimension n with n greater than or equal to 3, implies that the manifold is homothetic to a real ... More
Gamma-ray lens development status for a European Gamma-Ray ImagerNov 15 2006A breakthrough in the sensitivity level of the hard X-/gamma-ray telescopes, which today are based on detectors that view the sky through (or not) coded masks, is expected when focusing optics will be available also in this energy range. Focusing techniques ... More
Cosmography of the Local UniverseJun 01 2013Jun 13 2013The large scale structure of the universe is a complex web of clusters, filaments, and voids. Its properties are informed by galaxy redshift surveys and measurements of peculiar velocities. Wiener Filter reconstructions recover three-dimensional velocity ... More
Focusing of gamma-rays with Laue lenses: first resultsJul 09 2008We report on the first results obtained from our development project of focusing gamma-rays ($>$60 keV) by using Laue lenses. The first lens prototype model has been assembled and tested. We describe the technique adopted and the lens focusing capabilities ... More
New results on focusing of gamma-rays with Laue lensesOct 13 2009We report on new results on the development activity of broad band Laue lenses for hard X-/gamma-ray astronomy (70/100-600 keV). After the development of a first prototype, whose performance was presented at the SPIE conference on Astronomical Telescopes ... More
Derivation of Distances with the Tully-Fisher Relation: The Antlia ClusterJun 06 2008The Tully-Fisher relation is a correlation between the luminosity and the HI 21cm line width in spiral galaxies (LLW relation). It is used to derive galaxy distances in the interval 7 to 100 Mpc. Closer, the Cepheids, TRGB and Surface Brightness Fluctuation ... More
Circuit approach to photonic heat transportMar 16 2010Apr 06 2011We discuss the heat transfer by photons between two metals coupled by a linear element with a reactive impedance. Using a simple circuit approach, we calculate the spectral power transmitted from one resistor to the other and find that it is determined ... More
Long-range coherence and mesoscopic transport in N-S metallic structuresOct 26 1998Dec 22 1998We review the mesoscopic transport in a diffusive proximity superconductor made of a normal metal (N) in metallic contact with a superconductor (S). The Andreev reflection of electrons on the N-S interface is responsible for the diffusion of electron ... More
The Cosmic V-WebJun 11 2017The network of filaments with embedded clusters surrounding voids seen in maps derived from redshift surveys and reproduced in simulations has been referred to as the cosmic web. A complementary description is provided by considering the shear in the ... More
The Arrowhead Mini-Supercluster of GalaxiesSep 09 2015Superclusters of galaxies can be defined kinematically from local evaluations of the velocity shear tensor. The location where the smallest eigenvalue of the shear is positive and maximal defines the center of a basin of attraction. Velocity and density ... More
The Laniakea supercluster of galaxiesSep 02 2014Galaxies congregate in clusters and along filaments, and are missing from large regions referred to as voids. These structures are seen in maps derived from spectroscopic surveys that reveal networks of structure that are interconnected with no clear ... More
Fast motions of galaxies in the Coma I cloud: a case of Dark Attractor?Sep 13 2011We notice that nearby galaxies having high negative peculiar velocities are distributed over the sky very inhomogeneously. A part of this anisotropy is caused by the "Local Velocity Anomaly", i.e. by the bulk motion of nearby galaxies away from the Local ... More
Giant disk galaxies : Where environment trumps mass in galaxy evolutionFeb 01 2015We identify some of the most HI massive and fastest rotating disk galaxies in the local universe with the aim of probing the processes that drive the formation of these extreme disk galaxies. By combining data from the Cosmic Flows project, which has ... More
HyperLEDA. III. The catalogue of extragalactic distancesAug 15 2014We present the compilation catalogue of redshift-independent distances included in the HyperLEDA database. It is actively maintained to be up-to-date, and the current version counts 6640 distance measurements for 2335 galaxies compiled from 430 published ... More
Inherent thermometry in a hybrid superconducting tunnel junctionSep 29 2008Feb 08 2009We discuss inherent thermometry in a Superconductor - Normal metal - Superconductor tunnel junction. In this configuration, the energy selectivity of single-particle tunneling can provide a significant electron cooling, depending on the bias voltage. ... More
Differentiable Rigidity under Ricci curvature lower boundMay 25 2008May 28 2010In this article we prove a differentiable rigidity result. Let $(Y, g)$ and $(X, g_0)$ be two closed $n$-dimensional Riemannian manifolds ($n\geqslant 3$) and $f:Y\to X$ be a continuous map of degree $1$. We furthermore assume that the metric $g_0$ is ... More
Reconstructing cosmological initial conditions from galaxy peculiar velocities. I. Reverse Zeldovich ApproximationDec 12 2012We propose a new method to recover the cosmological initial conditions of the presently observed galaxy distribution, which can serve to run constrained simulations of the Local Universe. Our method, the Reverse Zeldovich Approximation (RZA), can be applied ... More
Cosmic Flows: Univ. Hawaii 2.2m I-band PhotometryMar 26 2011Within the "Cosmic Flows" project, I-band photometry of 524 relatively nearby galaxies has been carried out over the course of several years with the University of Hawaii 2.2m telescope and a camera with a 7.5 arcmin field of view. The primary scientific ... More
Divergence at low bias and down-mixing of the current noise in a diffusive superconductor-normal metal-superconductor junctionApr 27 2007Oct 26 2007We present current noise measurements in a long diffusive superconductor-normal-metal-superconductor junction in the low voltage regime, in which transport can be partially described in terms of coherent multiple Andreev reflections. We show that, when ... More
MoLUSC: A MOck Local Universe Survey ConstructorDec 06 2006This paper presents MoLUSC, a new method for generating mock galaxy catalogs from a large scale ($\approx 1000^3$ Mpc$^3$) dark matter simulation, that requires only modest CPU time and memory allocation. The method uses a small-scale ($\approx 256^3$ ... More
Probing Hybridization of a Single Energy Level Coupled to Superconducting LeadsJun 25 2015Electron transport through a quantum dot coupled to superconducting leads shows a sharp conductance onset when a quantum dot orbital level crosses the superconducting coherence peak of one lead. We study superconducting single electron transistors in ... More
Superconducting proximity effect in a mesoscopic ferromagnetic wireJun 12 1998Oct 30 1998We present an experimental study of the transport properties of a ferromagnetic metallic wire (Co) in metallic contact with a superconductor (Al). As the temperature is decreased below the Al superconducting transition, the Co resistance exhibits a significant ... More
Cosmological Simulations using Grid MiddlewareNov 28 2006One way to access the aggregated power of a collection of heterogeneous machines is to use a grid middleware, such as DIET, GridSolve or NINF. It addresses the problem of monitoring the resources, of handling the submissions of jobs and as an example ... More
Reconstructing cosmological initial conditions from galaxy peculiar velocities. III. Constrained simulationsDec 12 2012In previous works we proposed the Reverse Zeldovich Approximation (RZA) method, which can be used to estimate the cosmological initial conditions underlying the galaxy distribution in the Local Universe using peculiar velocity data. In this paper, we ... More
The 3D skeleton of the SDSSFeb 28 2006The length of the three-dimensional filaments observed in the fourth public data-release of the SDSS is measured using the {\em local skeleton} method. It consists in defining the set of points where the gradient of the smoothed density field is extremal ... More
Coherent Electron Transport in Superconducting-Normal Metallic FilmsMay 22 1997We study the transport properties of a quasi-two-dimensional diffusive normal metal film attached to a superconductor. We demonstrate that the properties of such films can essentially differ from those of quasi-one-dimensional systems: in the presence ... More
Cosmicflows-3May 05 2016The Cosmicflows database of galaxy distances that in the 2nd edition contained 8,188 entries is now expanded to 17,669 entries. The major additions are 2,257 distances that we have derived from the correlation between galaxy rotation and luminosity with ... More
Anatomy of Ursa MajorisNov 26 2012Nov 27 2012A nearby friable cloud in Ursa Majoris contains 270 galaxies with radial velocities 500 < VLG < 1500 km s^-1 inside the area of RA= [11h; 13h] and DEC= [+40deg; +60deg]. At present, 97 galaxies of them have individual distance estimates. We use these ... More
Hysteresis in superconducting short weak links and $μ$-SQUIDsSep 15 2010Thermal hysteresis in a micron-size Superconducting Quantum Interference Device ($\mu$-SQUID), with weak links as Josephson junctions, is an obstacle for improving its performance for magnetometery. Following the "hot-spot" model of Skocpol et al. [J. ... More
Electron transport in a mesoscopic superconducting / ferromagnetic hybrid conductorApr 05 2002Feb 03 2003We present electrical transport experiments performed on submicron hybrid devices made of a ferromagnetic conductor (Co) and a superconducting (Al) electrode. The sample was patterned in order to separate the contributions of the Co conductor and of the ... More
Long-Range Coherence in a Mesoscopic Metal near a Superconducting InterfaceOct 29 2001We identify the different contributions to quantum interference in a mesoscopic metallic loop in contact with two superconducting electrodes. At low temperature, a flux-modulated Josephson coupling is observed with strong damping over the thermal length ... More
The Dipole RepellerFeb 08 2017In the standard (LCDM) model of cosmology the universe has emerged out of an early homogeneous and isotropic phase. Structure formation is associated with the growth of density irregularities and peculiar velocities. Our Local Group is moving with respect ... More
Cosmic Bulk Flow and the Local Motion from Cosmicflows-2Mar 18 2015Full sky surveys of peculiar velocity are arguably the best way to map the large scale structure out to distances of a few times 100 Mpc/h. Using the largest and most accurate ever catalog of galaxy peculiar velocities "Cosmicflows-2", the large scale ... More
Reconstructing cosmological initial conditions from galaxy peculiar velocities. II. The effect of observational errorsDec 12 2012The Reverse Zeldovich Approximation (RZA) is a reconstruction method which allows to estimate the cosmic displacement field from galaxy peculiar velocity data and to constrain initial conditions for cosmological simulations of the Local Universe. In this ... More