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© 2015 Elsevier B.V. Electron Beam Melting (EBM), a powder bed additive layer manufacturing process, was used to produce Ti-6Al-4V specimens, whose microstructure, texture, and tensile properties were fully characterized. The microstructure, analyzed by optical microscopy, SEM/EBSD and X-ray diffraction, consists in fine α lamellae. Numerical reconstruction of the parent β phase highlighted the columnar morphology of the prior β grains, growing along the build direction upon solidification of the melt pool. The presence of grain boundary αGB along the boundaries of these prior β grains is indicative of the diffusive nature of the β→α phase transformation. Texture analysis of the reconstructed high temperature β phase revealed a strong pole in the build direction. For mechanical characterization, tensile specimens were produced using two different build themes and along several build orientations, revealing that vertically built specimens exhibit a lower yield strength than those built horizontally. The effect of post processing, either mechanical or thermal, was extensively investigated. The influence of surface finish on tensile properties was clearly highlighted. Indeed, mechanical polishing induced an increase in ductility - due to the removal of critical surface defects - as well as a significant increase of the apparent yield strength - caused by the removal of a ~150μm rough surface layer that can be considered as mechanically inefficient and not supporting any tensile load. Thermal post-treatments were performed on electron beam melted specimens, revealing that subtransus treatments induce very moderate microstructural changes, whereas supertransus treatments generate a considerably different type of microstructure, due to the fast β grain growth occurring above the transus. The heat treatments investigated in this work had a relatively moderate impact on the mechanical properties of the parts. ispartof: Materials Science and Engineering A, Structural Materials: Properties, Microstructure and Processing vol:652 pages:105-119 status: published

The use of additive manufacturing processes keeps growing in aerospace and biomedical industry. Among the numerous existing technologies, the Electron Beam Melting process has advantages (good dimensional accuracy, fully dense parts) and disadvantages (powder handling, support structure, high surface roughness). Analyzes of the surface characteristics are interesting to get a better understanding of the EBM operations. But that kind of analyzes is not often found in the literature. The main goal of this study is to determine if it is possible to improve the surface roughness by modifying some parameters of the process (scan speed function, number of contours, order of contours, etc.) on samples with different thicknesses. The experimental work on the surface roughness leads to a statistical analysis of 586 measures of EBM simple geometry parts.

Internal stress plays a key role in the design of materials that interact with hydrogen, for instance for sensing or storage applications. While increasing evidence in the literature points to an effect of internal stress on the equilibrium H-uptake, it is still an open question to what extent the hydriding kinetics can be affected by stress. Here, the hydriding kinetics of nanocrystalline Pd thin films is studied with varying degrees of growth-induced internal stress levels. The experimental technique consists of a high-resolution curvature measurement set-up. After mounting the sample inside a high-vacuum chamber, a H-containing gas mixture is introduced to generate instantaneously a given hydrogen partial pressure (pH2) inside the chamber. The resulting interaction of H with the Pd layer then leads to an expansion of the thin-film system constrained by the underlying substrate, inducing in turn a change in the sample curvature. The curvature evolution, obtained in situ at different , is first interpreted with a self-consistent kinetic model in order to identify the different rate-limiting steps during a hydriding cycle. Next, the corresponding rate constants are calculated, as well as their variation with internal stress. The internal stress does not affect the rate constant of the adsorption-limited regime in the range 60–450 MPa, leading to an average value of 1.1 ± 0.2 × 1021 mbar−1 s−1 over the experimentally covered pH2 range, 1–10 mbar. As to the absorption-limited regime, a significant stress effect was recorded on the absorption rate constant of the very initial stages of hydriding, leading to an activation volume of 17.6 ± 2.3 A3 for H-absorption into our Pd thin films. This value, combined with an initial internal tensile stress of the order of 450 MPa, leads to a decrease of the activation energy for H-absorption of 3 kJ mol−1. This effect induces up to a factor 3 increase in the room-temperature absorption rate in the initial stages of hydriding.

The fast growing of Additive Manufacturing (AM) leads us to study the functionality of parts built by these processes. Recently, the Electron Beam Melting process and the Direct Melting Laser Sintering process are used to produce parts in the biomedical and aeronautical fields. The Ti6Al4V is largely used in these fields. This paper present an experimental study of machining Ti6Al4V alloy produced by Electron Beam Melting (EBM) before and after HIPping (Hot Isostatic Pressing). The results shows that the hipping has no significant influence on specific cutting pressure.

In this work, we will report on scientific efforts aimed at unraveling the quantitative effect of elastic strain on the electro-optical behaviour of Al-doped zinc oxide (AZO). AZO thin films have been deposited by reactive magnetron sputtering to thicknesses from 300 to 500 nm, both on extra-clear glass substrates as well as on oxidised Si wafers. This resulted in both cases in polycrystalline, strongly textured (002) films. During deposition, the internal stress evolution in the growing film was monitored in-situ using high resolution curvature measurements. The resulting growth-induced elastic strain, which was found to depend heavily on the oxygen partial pressure, could further be modulated by appropriately choosing the deposition temperature. The latter also induces an additional extrinsic thermal stress component, whose sign depends on the substrate used. As such, a wide range of biaxial internal stresses could be achieved, from −600 MPa in compression up to 800 MPa in tension. The resulting charge carrier mobilities, obtained independently from room temperature Hall measurements, were found to range between 5 and 25 cm2/V s. Interestingly, the maximum mobility occurred at the zero-stress condition, and together with a charge carrier concentration of about 8 × 1020 cm−3, this gave rise to a resistivity of only 300 μΩ cm. From the stress-dependent optical transmission spectra in the range of 200–1000 nm, the pressure coefficient of the optical bandgap was estimated from the corresponding Tauc plots to be 31 meV/GPa, indicating a very high strain-sensitivity as well.

Transparent and conductive ZnO:Al films were deposited by RF magnetron sputtering on opaque (Si/SiO2) or transparent (glass) substrates. The internal stress evolution has been measured in situ using a high resolution 2D curvate measurement technique. Internal tensile or compressive stresses were generated, depending on the sputtering pressure, oxygen addition level and substrate temperature. The origin of the observed stress level is correlated with factors affecting the film growth mechanism, and the relation with the electro-optical properties of the resulting transparent and conductive oxide films is highlighted.

The first crystal structures of a dinuclear iron(II) complex with three N1,N2-1,2,4-triazole bridges in the high-spin and low-spin states are reported. Its sharp spin transition, which was probed using X-ray, calorimetric, magnetic, and (57)Fe Mossbauer analyses, is also delineated in the crystalline state by variable-temperature fluorimetry for the first time.

Being the exponent of the so-called "bottom-up" approach, self-assembled structures are now-a-days attracting a lot of attention in the fields of science and technology. In this work, we show that nanoscale self-assembled arrays used as templates can provide periodic modulation in superconducting thin films by studying their vortex pinning properties. In this work advantage was made of the fact that self-organized assemblies of identical units such as colloidal crystals and anodic aluminum oxide provide extended periodic topographic surfaces. By directly growing Nb on top of these self-assembled arrays, the templating effect was exploited in order to achieve triangular and honeycomb arrays of pinning centers in thin superconducting films. We show experimentally that periodic matching is achieved in both systems at magnetic fields, well above those present in lithographically prepared pinning arrays (up to 1 T!). Furthermore, we demonstrate in the case of anodic aluminum oxide that the presence of porous antidots in Nb not only provides strongly increased critical currents but also conserves matching at temperatures well below the critical temperature. The studies conducted on these systems indicate that the method of template growth might be considered as a viable alternative for the incorporation of periodic pinning arrays in superconducting applications of today and the future. (c) 2008 Elsevier B.V. All rights reserved.

The effects of the solution pH and deposition potential on the structural and magnetic properties in arrays of electrodeposited CoCu nanowires with low Cu content have been studied combining ferromagnetic resonance, magnetometry and electron transmission microscopy. It is shown that, depending on the synthesis parameters, the average crystallographic structure can be controlled, giving rise to sensible changes in the effective crystal anisotropy field which varies from -4.05 to +2.75 kOe. It is also shown that in CoCu/Cu multilayered nanowires, the preferential structure of the CoCu-magnetic layer can also be controlled by both pH and deposition potential, opening an interesting route for designing multilayered CoCu/Cu nanowires with controlled and alternated crystal anisotropy.

We present a study of magnetization and transport properties of superconducting Nb thin films deposited on nanoporous aluminium oxide templates. Periodic oscillations in the critical temperature vs. field, matching effects in fields up to 700 mT and strongly enhanced critical currents were observed. These fields are considerably higher than those typical for periodic pinning arrays made by lithographic techniques, which reflects the benefits of nanostructuring superconductors by using self-organized growth. This method provides a periodic pinning potential with sub-100 nm spacing between the pinning centers, which enhances vortex pinning in broad field and temperature ranges.

A reliable method enabling electrical measurements on single nanowires prepared by electrodeposition in an alumina template is described. This technique is based on electrically controlled nanoindentation of a thin insulating resist deposited on the top face of the template filled by the nanowires. We show that this method is very flexible, allowing us to electrically address single nanowires of controlled length down to 100 nm and of desired composition. Using this approach, current densities as large as 10(9) A cm(-2) were successfully injected through a point contact on a single magnetic multilayered nanowire. This demonstrates that the technique is very promising for the exploration of electrical spin injection in magnetic nanostructures.

This article is focused on the use of electrodeposition and of various nanoporous templates for the fabrication of metallic nanowires made from single metals (Ni, Co, Pb, Sn), alloys (NiFe, CoFe, CoPt), and multilayers (Co/Cu, NiFe/Cu). An overview is given of our recent studies performed on both magnetic and superconducting nanowires. Using different approaches entailing measurements on both single wires and arrays, numerous interesting physical properties have been identified in relation to the nanoscopic dimensions of these materials. Finally, various novel applications of the nanowires are also discussed.

Magnetization curves well below T-c of a lead nanowire array electrodeposited under pulsed voltage conditions are considered. Numerical simulations based on a two-dimensional resolution (2D model) of the Ginzburg-Landau (GL) equations for cylindrical configurations have also been developed. By freely adjusting the GL phenomenological lengths lambda(T) and epsilon(T), the experimental magnetization curves are reproduced to within a 10% error margin. The 2D model also allows us to check the cylindrical symmetry of the obtained configurations. Beyond the experimental-theoretical agreement, the question of whether the GL model remains valid far below T-c is also addressed. The temperature dependence of the adjusted characteristic lengths is compared with different theoretical and empirical laws. The most satisfactory agreement is achieved for the Gorter-Casimir two-fluid model. A comparison with a lead nanowire array electrodeposited under constant voltage conditions allows us to distinguish both samples in terms of their electronic mean free paths. The characterization of the latter quantities concurs perfectly with the experimental expectation given the different electrodeposition techniques.

Nanowires grown by electrodeposition using nanoporous template have attracted much attention due to the simplicity of this technique for preparing nano-scaled materials. We present here a standard way to fabricate lead or tin nanowire arrays. We also present some of their superconducting properties directly affected by the reduced dimensions; these are the magnetic flux penetration and confinement in nanowires having a diameter only a few times the magnetic penetration length, as well as the formation of phase-slips centres in nanowires having a diameter smaller than the coherence length.

We report on the transport properties of single superconducting lead nanowires grown by an electrodeposition technique, embedded in a nanoporous track-etched polymer membrane. The nanowires are granular, have uniform diameter of similar to40 nm and a very large aspect ratio (similar to500). The diameter of the nanowire is small enough to ensure a I D superconducting regime in a wide temperature range below T-c. The non-zero resistance in the superconducting state and its variation caused by fluctuations of the superconducting order parameter were measured versus temperature, magnetic field, and applied DC current (or voltage). The current induced breakdowns in the V-1 characteristics may be explained by the formation of phase slip centers. Moreover, DC voltage driven measurements reveal the existence of a new S-shape behavior near the formation of these phase slip centers. (C) 2003 Elsevier B.V. All rights reserved.

Beyond the well-known Abrikosov and giant vortex configurations, new solutions to the Ginzburg–Landau model corresponding to vortices of integer and half-integer winding number are described. Phase diagrams (Bext, Energy) and magnetization curves have been determined, aiming towards an understanding of the magnetic properties of lead nanowires and the possible consequences of such solutions with respect to the switching mechanism between vortex states in mesoscopic superconductors.

Theoretical and experimental magnetizations of lead nanowire arrays well below the superconducting transition temperature Tc are described. The magnetic response of the array was investigated with a SQUID magnetometer. Hysteretic behaviour and phase transitions have been observed in sweeping up and down the external magnetic field at different temperatures. The Meissner and Abrikosov states were also experimentally observed in this apparently type-I superconductor. This fact brings to the fore the non-trivial behaviour of the critical boundary κ c ( = 1/ in bulk materials) between type-I and type-II phase transitions at mesoscopic scales. The time-independent Ginzburg-Landau equations particularized to cylindrically symmetric configurations enable one to explain and reproduce the experimental magnetization curves within 10% of error.

We report on the transport properties of single superconducting lead nanowires grown by an electrodeposition technique, embedded in a nanoporous track-etched polymer membrane. The nanowires are granular, have a uniform diameter of similar to40 nm and a very large aspect ratio (similar to500). The diameter of the nanowires is small enough to ensure a one-dimensional superconducting regime in a wide temperature range below T-c. The non-zero resistance in the superconducting state and its variation caused by fluctuations of the superconducting order parameter were measured versus temperature, magnetic field, and applied dc current (or voltage). The current-induced breakdowns in the voltage-current characteristics may be explained by the formation of phase slip centres. Moreover, dc voltage driven measurements reveal the existence of a new S-shape behaviour near the formation of these phase slip centres.

Mesoscopic superconducting lead nanowires with high aspect ratio and diameter ranging from 40 to 270 nm have been grown by electrodeposition inside nanoporous polycarbonate membranes. Nanowires with a diameter less than 50 nm were insulators due to a poor crystal structure. The others are shown to be type II superconductors because of their small electronic mean free path, instead of being type I which is usual for the bulk form of lead. An increase in the thermodynamic critical field H-c is observed and is attributed to the small transversal dimension leading to an incomplete Meissner effect. Finally, it is demonstrated that this enhancement agrees with numerical simulations based on the Ginzburg-Landau theory. (C) 2002 Elsevier Science B.V. All rights reserved.

By electrodeposition of tin inside the pores of a polycarbonate template, nanowires were grown, out of which a single one was contacted electrically so as to form a quasi-one-dimensional superconductor (diameter: 50 nm). A resistive phase-slip center appears as a response to a pulse of supercritical current. Measuring its resistance, and its time of nucleation, gives access to the electron inelastic lifetime, and to the gap relaxation time, respectively, both in the nanosecond range. Finally, the threshold current for passage into the fully normal state indicates a good thermal contact with the polycarbonate matrix. (C) 2004 American Institute of Physics.

Arrays of granular superconducting Pb and Sn nanowires (40 - 55 nm in diameter and 22 or 50 mum long) have been prepared by electrodeposition in nanoporous membranes. A simple technique has been developed to perform electrical transport measurement on a single nanowire. By sweeping the dc current inside the nanowire, we observed the formation of phase-slip-centers far below the critical temperature. In contrast, in voltage-driven experiments, an interesting S-shaped behavior has been observed in the nucleation region of these phase-slip-centers. (C) 2003 American Institute of Physics.

Nanocrystalline Pd films were produced by electron-beam evaporation and sputter deposition. The electron-beam-evaporated films reveal randomly oriented nanograins with a relatively high density of growth twins, unexpected in view of the high stacking fault energy of Pd. In contrast, sputter-deposited films show a clear 〈1 1 1〉 crystallographic textured nanostructure without twins. These results provide insightful information to guide the generation of microstructures with enhanced strength/ductility balance in high stacking fault energy nanocrystalline metallic thin films.

The critical current of a niobium type II superconducting loop has been measured far below the critical temperature using contacts applied symmetrically or asymmetrically around the loop. The magnetic field dependence of the critical current allows a direct observation of the circulating current resulting from the fluxoid quantization and presents a saw-tooth behavior. The periodicity is given by a flux quantum through the outer area of the loop. Despite the presence of many vortices at high magnetic fields, the circulating current finds its way in between them and still has an impact on the total critical current of the loop. Macroscopic quantum coherence effects in such a niobium loop allow observing single quanta changes of the fluxoid up to a magnetic field of 1.2 T.

Applying current in type-II superconducting sub-micron size structures often leads to a discontinuity of the current-voltage characteristic as the instability current is reached. Also voltage-bias mode allows to avoid such an abrupt switch to the normal state, and gives a relevant outlook of the involved resistive phenomenons. Current and voltage-bias measurements on NbN microbridges with a constriction are reported here as a function of temperature and transverse magnetic field. Starting from a 75nm-thick sputtered film, 160nm-wide microstrips were patterned with an half-wide section constriction in their middle. From the current-bias curves it appears that the discontinuities are due to a flux flow instability that rapidly evolves in a hot-spot. Moreover applying the voltage reveals several dissipative states that leads to successive S-shaped current oscillations in a small current range. Formation of vortex channels can be considered to explain these features.

Dense arrays of ordered ferromagnetic nanowires have been used to create periodic magnetic pinning centers in thin superconducting NbN films. The nanowires were electrodeposited in a highly ordered porous alumina membrane and the thin NbN film was deposited on top of the perpendicularly oriented magnetic nanowires. Matching effects have been observed up to 2.5 T (11th matching field) and are maintained at low temperature. An appreciable enhancement of the superconducting properties is observed. At low fields, a hysteretic behavior in the magnetoresistance is found, directly related to the magnetization processes of arrays of interacting single domain ferromagnetic nanowires. (C) 2009 American Institute of Physics. [doi:10.1063/1.3276557]

The interest in the template-based synthesis of nanomaterials and nanostructures is continuously increasing due to the advantageous features offered by the templates and the ease of processing a large number of nanostructures in parallel. In recent years, nanoporous anodic aluminum oxide (AAO) has been intensively studied and used for that purpose. [1] At present, it is considered one of the most promising templates [2] mainly because of its unique features, which include easily tunable geometrical parameters, mild preparation conditions, and resistance to high temperatures. AAO, whichisatypicalself-orderednanopore-arraymaterialformed by the electrochemical oxidation of Al in acidic solutions, is an excellent starting host material for the fabrication of various nanomaterials and nanostructures. It possesses a hexagonally packed arrangement of nanoscale-sized straight blind holes aligned perpendicular to the surface. The voids of the nanoscale-channeled structure are typically filled with various materials and heterostructures using electrochemical or chemical vapor deposition methods after the elimination of the oxide barrier layer that closes the bottom ends of the holes. While this barrier layer is typically considered undesirable and eliminated, herein we emphasize that the surface of this layer possesses an ordered array of hemispheres that can also be used as a very interesting template. We describe the advantages of the ordered bumpy surface for creating artificial superconducting pinning centers in Nb films deposited on it.

Transport properties of a superconducting NbN nanowire are studied experimentally and theoretically. Different attached leads (superconducting contacts) allowed us to measure current-voltage (I-V) characteristics of different segments of the wire independently. The experimental results show that with increasing the length of the segment the number of jumps in the I-V curve increases indicating an increasing number of phase-slip phenomena. The system shows a clear hysteresis in the direction of the current sweep, the size of which depends on the length of the superconducting segment. The interpretation of the experimental results is supported by theoretical simulations that are based on the time-dependent Ginzburg-Landau theory, the heat equation has been included in the Ginzbur-Landau theory.

Using appropriate electrodeposition conditions, it is shown that the structural and magnetic properties of arrays of Co and CoCu/Co nanowires can be controlled. The hcp c axis orientation can be oriented parallel or perpendicular to the wire axis simply by changing the pH of the electrolytic solution and/or deposition rate. This selected orientation of the c axis leads to a drastic change in overall magnetic anisotropy and is promising for the fabrication of spin valves structures by electrodeposition.

We performed photoluminescence experiments on colloidal, Co2+-doped ZnO nanocrystals in order to study the electronic properties of Co2+ in a ZnO host. Room temperature measurements showed, next to the ZnO exciton and trap emission, an additional emission related to the Co2+ dopant. The spectral position and width of this emission does not depend on particle size or Co2+ concentration. At 8 K, a series of ZnO bulk phonon replicas appear on the Co2+-emission band. We conclude that Co2+ ions are strongly localized in the ZnO host, making the formation of a Co2+ d-band unlikely. Magnetic measurements revealed a paramagnetic behaviour. (c) 2005 Elsevier B.V. All rights reserved.

Experimental results on the phase slip process in superconducting lead nanowires are presented under two different experimental conditions: constant applied current or constant voltage. Based on these experiments we established a simple model which gives us the condition of the appearance of phase slip centers in a quasi-one-dimensional wire. It turns out that the competition between two relaxations times (relaxation time of the absolute value of the order parameter $\tau_{|\psi|}$ and relaxation time of the phase of the order parameter in the phase slip center $\tau_{\phi}$) governs the phase slip process. Phase slip phenomena, as periodic oscillations in time of the order parameter, is possible only if the gradient of the phase grows faster than the value of the order parameter in the phase slip center, or equivalently if $\tau_{\phi}, Comment: 13 pages, 15 figures

Applying a constant voltage to superconducting nanowires we find that its IV-characteristic exhibits an unusual S-behavior. This behavior is the direct consequence of the dynamics of the superconducting condensate and of the existence of two different critical currents: j_{c2} at which the pure superconducting state becomes unstable and j_{c1}, Comment: 4 pages, 5 figures, replaced with minor changes

We have fabricated Pb, Sn and multilayered Pb/Cu nanowires using electrodeposition in nanoporous template. Single wires 50 nm in diameter and 20 mu m long are contacted with either An or Pb (superconducting) films using a self-contacting technique. We have measured Pb and Sn wires with Pb contacts and careful filtering. The proximity effect is probe in this geometry with the Sn nanowire that becomes superconducting near the Pb critical temperature due to the Pb contacting layers. (c) 2007 Elsevier B.V. All rights reserved.

Electrical transport measurements were performed on NbN multicontact microstrips in order to investigate the non-equilibrium dissipative states in highly disordered granular superconducting nanostructures. By applying a dc voltage-bias, a peculiar discontinuous normal phase propagation was observed in a current interval well below the switching point. These stabilized resistive states are explained within the framework of a localized normal hotspot maintained by Joule heating. The thermal healing length of our NbN microstrips is estimated by taking into account both kinds of heat transfer (i.e. by conduction within the microstrip and by surface heat transfer through the substrate). It appears that the estimated healing length properly matches the length associated with a normal region across the whole width and whose resistance is given by the difference of resistance between two nearest intermediate dissipative states as observed in the voltage-biased curves.

Electrical transport measurements were performed on superconducting NbN multicontact microstrips in order to investigate non-equilibrium dissipative states in type-II nanostructures. Current-biased and voltage-biased approaches point out the ability to stabilize a normal phase that grows discontinuously, in opposition to the usual self-spreading hotspot propagation. Results obtained by applying a dc voltage to two segments in series support this idea of a peculiar hotspot expansion. This last voltage-biasing configuration, which involves five contacts, could be used in the future to distinguish more easily between hotspot discontinuous growth and phase-slippage mechanisms.

Lead and tin nanotubes were synthesized by electroless deposition in a nanoporous polymer membrane without sensitization, activation or a reducing agent. A thick Pb or Sn layer is evaporated on one side of the membrane and provides the metallic ions needed to grow the tubes in an aqueous solution. The nanotubes' geometry and composition were investigated by means of electron microscopy, energy dispersive x-ray spectroscopy and ultramicrotomy. Electrical measurements obtained on such superconducting nanotubes are compared with solid wire characteristics. This spontaneous growth could explain some recent results obtained on superconducting nanowires showing an anomalous long-range proximity effect.

A flux qubit readout scheme involving a dispersive technique coupled to a microstrip superconducting quantum interference device (SQUID) amplifier has been tested experimentally. Thanks to the almost quantum limited noise of this amplifier at low temperature, this readout device is very promising for a design with actual qubits. Its proof of principle and low noise performance have been tested by simulating the qubit presence by applying a tiny flux change in the input SQUID. The resonant frequency of the amplifier is adjusted in situ with a varactor diode to approach the frequency of the tank circuit. Two operating modes (crossing or anticrossing regime) were identified.

The barrier layer of self-ordered anodized aluminium oxide, which is grown from an aluminium foil, has been revealed by a selective chemical etching of the remaining aluminium. The surface obtained in this way consists of a triangular lattice of bumps with 100 nm spacing, and heights of approximately 50 nm. Using this surface as a template for controlling the pinning in thin superconducting films, superconducting Nb was deposited with different thicknesses and under different deposition angles. The evaporation under a 30 degrees angle shows an asymmetric pinning potential composed of two triangular lattices having different pinning strengths. Matching effects are observed up to 1T. Matching effects are also maintained at relatively low temperature.

Using nanoporous media as templates for electrodeposition, we have fabricated multilayered Pb/Cu nanowires 50 nm in diameter and 20 μ m long with Cu layer thicknesses as low as 10 nm. This was achieved by using a single-bath technique and a precise selection of the copper deposition potential to limit the redissolution of lead when the potential is raised to electrodeposit the more noble metal. Such superconductor/normal multilayered nanowires show interesting magnetoresistance properties at a low magnetic field that may be related to the proximity effect, which can therefore be investigated in a quasi-one-dimensional geometry. (C) 2005 American Institute of Physics.