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The synthesis of phase‐pure ternary solutions of tetradymite‐type materials (BixSb1−x)2Te3 (x=0.25; 0.50; 0.75) in an ionic liquid approach has been carried out. The nanoparticles are characterized by means of energy‐dispersive X‐ray spectroscopy (EDX), powder X‐ray diffraction (PXRD), scanning electron microscopy (SEM), and transmission electron microscopy. In addition, the role of different processing approaches on the thermoelectric properties ‐ Seebeck coefficient as well as electrical and thermal conductivity ‐ is demonstrated.

3D topological insulators (TI) host surface carriers with extremely high mobility. However, their transport properties are typically dominated by bulk carriers that outnumber the surface carriers by orders of magnitude. A strategy is herein presented to overcome the problem of bulk carrier domination by using 3D TI nanoparticles, which are compacted by hot pressing to macroscopic nanograined bulk samples. Bi2 Te3 nanoparticles well known for their excellent thermoelectric and 3D TI properties serve as the model system. As key enabler for this approach, a specific synthesis is applied that creates nanoparticles with a low level of impurities and surface contamination. The compacted nanograined bulk contains a high number of interfaces and grain boundaries. Here it is shown that these samples exhibit metallic-like electrical transport properties and a distinct weak antilocalization. A downward trend in the electrical resistivity at temperatures below 5 K is attributed to an increase in the coherence length by applying the Hikami-Larkin-Nagaoka model. THz time-domain spectroscopy reveals a dominance of the surface transport at low frequencies with a mobility of above 103 cm2 V-1 s-1 even at room temperature. These findings clearly demonstrate that nanograined bulk Bi2 Te3 features surface carrier properties that are of importance for technical applications. © 2021 The Authors. Small published by Wiley-VCH GmbH.

An electrochemical and in situ magnetic study is conducted to identify key parameters for room-temperature electrochemical (magneto-ionic) switching of magnetism by repeated oxidation and reduction of iron species in aqueous KOH. Potentiodynamic routines allow to distinguish the reaction potentials and, in contrast to measurements on bulk Fe electrodes, uncover the importance of dissolution processes in thin film geometry. The pH of the solution affects both dissolution and reduction to metallic iron. The magnetic properties strongly depend on the applied oxidation and reduction potentials. Large magnetic changes are obtained when switching between the potential of reduction to metallic iron and intermediate oxidation potentials, revealing an influence of the structure of the oxide layer. Keywords: Magnetoelectric effect, Magnetic films, Magnetoionic effect, Oxidation, Reduction, Iron

Fe–Pd alloy films containing about 30 at.% Pd were electrochemically deposited using a double complexed ammonia-sulfosalicylic acid based aqueous electrolyte. The impact of individual electrolyte components on the structure, morphology and composition of the films has been investigated by means of XRD, EDX and electrochemical methods. Significant changes in the phase structure were observed when varying the electrolyte pH, the concentration of SSA or adding small amounts of Cu2+ ions to the electrolyte. The results are discussed in terms of the direct electrochemical preparation of a shape memory active material.

In order to reverse the magnetization of small ferromagnetic particles it is necessary to overcome an energy barrier, which is mainly defined by the magnetic anisotropy. Usual reversal stimuli include the application of static or time-dependent external magnetic fields, thermal activation, spin transfer torque, or combinations thereof. Here, we report on repeated, quasi-periodic magnetization reversal in single-domain particles that are exposed to a constant magnetic field perpendicular to the magnet's easy axis. The continuous sequence of reversals is induced by torsional oscillations of the magnet's anisotropy landscape, which are caused by angular oscillations of the magnet's body. In our experiments, a nickel nanowire constitutes both a mechanical resonator and a nanomagnetic sample with uniaxial anisotropy. We measure the transient flexural vibration behavior by electron beam based methods and find strong signatures of periodic magnetization switching between two magnetic states of the nanowire. Our system can be modeled as a driven damped harmonic oscillator under the influence of switchable magnetostatic interactions.

Solid state refrigeration is of great interest due to its potential application in electronic and optoelectronic systems. Nowadays, macroscopic thermoelectric coolers are part of such systems and their cooling performance and reliability are well proven. However, the feasibility of microstructuring such kind of devices by means of photolithographic techniques, opens the possibility of integration on a chip for better local thermal management. Together with previous facts, electrodeposition processes are well known to be low cost, highly scalable and compatible with lithographic techniques. In this work we report on the fabrication of BiTe-based Micro-Thermoelectric Coolers by means of a mixed process flow involving photolithography and electrodeposition techniques. Materials and geometry of the device have been chosen to optimise the cooling performance on an integrated photonic system.

Reversible control of magnetism at the metal/electrolyte interface offers great application potential for multifunctional magnetic devices. Here, the electrode–electrolyte interactions and the charging of FePt alloy films in LiPF 6 in dimethyl carbonate(DMC)–ethylene carbonate (EC) are analysed in comparison to the pure metals Fe and Pt. The main electrode processes are Li deposition and dissolution, Fe dissolution and redeposition, and reduction as well as oxidation processes of impurities and electrolyte. Fe is found to be more stable against anodic dissolution in FePt films. Pt attenuates electrode passivation and catalyses impurity reduction reactions. This results in a cathodic potential limit of 1.8 V vs. Li/Li + for charging FePt films without side reactions. Subsequently, ultrathin textured FePt films promising large voltage induced magnetic surface effects where used as electrodes. Magnetic properties during charging were monitored by an in situ setup based on the anomalous Hall effect. Marginal Fe dissolution at the surface above 3 V vs. Li/Li + is detected by the in situ measurement and limits the upper charging potential. In consequence, a potential window of 1.2 V for charging the FePt films is obtained. In this potential range a large reversible change of magnetic moment is detected, which is attributed to reversible redox processes in the native iron oxide surface layer.

Due to its high magnetostriction and good mechanical properties Fe 80 Ga 20 is interesting for magnetostrictive microactuators and sensors. Here we use electrodeposition to grow Fe–Ga films onto Au and Pt coated Si substrates by potentiostatic and pulse potential deposition. Composition, microstructure and structure are analysed. The desired composition of Fe 80 Ga 20 was obtained at −1.4 V SCE and −1.5 V SCE , respectively. The origin of low reproducibility and high oxygen content up to 50 at.% is investigated. Optimum deposition conditions to achieve dense, homogeneous films with low oxygen content are identified. In these films the saturation magnetization reaches a maximum value of 1.7 T confirming the high quality of electrodeposited films.

Fe−Pd nanowires for MSM applications are obtained by electrodeposition from a stable complexed Fe3+/Pd2+ electrolyte. By application of an alternating potential mode, a composition close to the intended Fe70Pd30 alloy can be achieved. In particular, the second pulse step potential E2 is identified to be the key parameter for continuous, defect-free nanowires. The adjustment of E2 to more positive values avoids the formation of Pd-rich segments as well as the blocking of pores by hydrogen bubbles. Detailed TEM and structural investigations reveal a bcc Fe−Pd structure and nanocrystalline deposits with grain sizes in the 5 nm range. The observed structural features are attributed to the electrochemical processes within the constraint geometry of the nanoporous template. The magnetic properties of these nanowires are controlled by shape anisotropy as well as magnetostatic interactions.

Co-rich Co-Pt alloy films have been grown by electrodeposition on Au buffer layer. Detailed texture measurements have been performed in order to understand the dependence of magnetic properties on phase composition and texture. X-ray analysis in Bragg-Brentano geometry shows that films seem to consist of hexagonal closed packed (hcp) or fcc phase. Due to similar lattice spacing of the densely packed planes of both possible phases, the (111) fcc and (002) hcp planes of Co-Pt and also the higher order reflections coincide. As a result, the information supplied by X-ray diffraction was of limited value. Hence pole figure measurements are used which determine the directional distribution of planes with a selected spacing. Here we present an approach to use pole figure measurements for phase identification. We show that this method allow a direct correlation with the magnetic properties, in particular with the magnetocrystalline anisotropy and magnetic texture.

Block copolymer (BCP) thin films have received enormous interest for possible applications in nanotechnology due to their self-assembled structure formation. However, synthesis of polymers with desired chemical and physical properties sometimes is not possible. During the past 6 years, our group developed a method to introduce certain functionality into self-assembled structures via the formation of supramolecular assemblies from BCPs and low molecular weight additives. Among several other materials, the most noteworthy is a system consisting of polystyrene-block-poly(4-vinylpyridine) and 2-(4′-hydroxybenzeneazo) benzoic acid which has been used as nanotemplate for the fabrication of materials with potentially exceptional electrical, optical, or magnetic properties. The present article summarizes the research done at our group on fundamental aspects of microphase separation in these supramolecular assemblies and also their further use as templates for nanofabrication.

Magnetic nanowire arrays allow studying magnetism at the nanoscale and have broad application areas. Here we review our recent experiments on tailoring the structure and microstructure of electrochemically grown elemental (Fe, Ni, Co) and alloy (Co-Pt) magnetic nanowires. The comparison of these different materials allows identifying the role of shape, magnetocrystal-line and magnetoelastic anisotropies as well as magnetostatic interactions.

Due to their high aspect ratio, magnetic nanowires are interesting for various applications. Fe nanowires are of particular interest due to their high magnetization, which suggests high shape anisotropy is possible. Here, we show how the electrodeposition process can be adapted to the constraints of a high aspect ratio template in order to approach an ideal behaviour of smooth and pure Fe nanowires. An adjustment of the Fe2+ concentration and the addition of H3BO3 result in smooth and continuous nanowires; saturation polarization is achieved, together with an anisotropy field of up to 70% compared to pure Fe. Mossbauer spectroscopy reveals a negligible amount of impurities. Together with magnetic measurements we show that shape anisotropy aligns the preferential magnetization axis along the wire axis.

Patterned media for future ultrahigh-density magnetic data storage can be prepared by electrodeposition into ordered arrays of nanostructured templates. Diblock copolymer templates have been proposed as a promising alternative to alumina templates. They possess smaller feature sizes than alumina and thereby allow for higher storage densities. Templates with pore diameters of ∼8 nm have been fabricated by dip-coating a conducting substrate into a solution of polystyrene- block -poly(4-vinylpyridine) (PS-b-P4VP) and 2-(4′-hydroxybenzeneazo) benzoic acid (HABA). A vapor annealing step was interposed for better ordering. The pores are opened by dissolving the HABA from the supramolecular assembly and afterwards filled by electrodeposition. Fe–Pt and Co–Pt alloys are the materials of choice for filling the pores due to their hard magnetic properties like high coercivity and anisotropy. Co-rich Co 80 Pt 20 was chosen for this study because it does not require post annealing as in the case of ordered L1 0 CoPt or FePt. Continuous films have been deposited in order to identify the optimum deposition conditions and the influence of deposition current density on chemical composition, growth morphology, and structural and magnetic properties has been studied systematically. The first results on templates electrochemically filled with Co–Pt are presented together with an analysis of their magnetic properties.

Fe-Pt films with an Fe/Pt ratio close to one can be electrodeposited from an FeSO 4 -H2PtCl 6 -Na 2 SO 4 electrolyte. At the deposition potential, the hydrogen evolution and the reduction of the Pt complex are diffusion limited, and Fe overpotential deposition has not yet set in. The sources of the Fe incorporation are iron hydroxide formation together with Fe underpotential deposition due to Fe-Pt alloy formation. Mossbauer measurements show that the iron in the iron hydroxide is predominantly Fe(III). For stoichiometry reasons, a Pt-rich Fe-Pt phase must be present in addition to the Fe(III)-hydroxide. The Fe 3+ that takes part in the hydroxide formation is produced in the electrolyte by the oxidation of Fe 2+ by the complexed Pt ion. This exchange reaction results in a significantly higher Fe 3+ content in the FeSO 4 -H 2 PtCl 6 -Na 2 SO 4 electrolyte in comparison to the same electrolyte without H 2 PtCl 6 . Fe(lII)-hydroxide formation can be depressed by adding citric acid, that acts as buffering and complexing agent. This leads to a lower iron content of the deposits. The Fe/Pt ratio close to one that is needed for hard magnetic properties can, however, only be achieved with a significant incorporation of iron hydroxide.

Electrodeposition from a single bath is used to prepare Fe-Pt films and Fe/Pt multilayers for hard magnetic film applications. Electrodeposition of Fe-Pt is not a simple codeposition of Fe and Pt. Large amounts of oxygen are found in as deposited films. In addition, Fe incorporation takes place at potentials positive to the equilibrium reduction potential of Fe2+. The analysis of the electrode processes and of potentiostatically deposited films indicate that both, iron hydroxide incorporation and underpotential deposition of Fe must be considered. The oxygen content could not be reduced in homogeneous films with an Fe-Pt ratio of 1.0 as the depression of iron hydroxide formation also leads to inhibition of iron incorporation. However, the alternating deposition of Fe-rich and Pt-rich layers, both with low oxygen content, leads to a lower integral oxygen content for an Fe/Pt ratio of 1.0. H2 annealing of the multilayered films reduces remaining iron (hydro)oxides and results in high coercivities and remanences.

Co–Pt thin films were prepared using single bath electrodeposition. The deposition process was analysed using current-potential and electrochemical quartz microbalance (EQCM) measurements. As-deposited films were annealed to achieve the L 1 0 phase. Under optimised conditions, a maximum coercivity of 1.17 T and a maximum remanence of 0.7 T are achieved. The δ J analysis of the hysteresis loops reveals exchange coupling in the annealed film. Deposition process, phase formation, and magnetic properties are discussed in comparison to electrodeposited Fe–Pt films.

The local microstructure of Fe-Ga nanowires is investigated considering dependence on the deposition technique. Using a complexed electrolyte, smooth and homogeneous Fe80Ga20 nanowires are deposited into anodic aluminum oxide templates by either applying pulse potential or potentiostatic deposition technique. At optimized deposition conditions the wires show the desired composition of Fe80±2Ga20±2 without a gradient along the growth direction. Composition distribution, structure and microstructure are examined in detail and reveal only minor differences. Line EELS and crystal lattice measurements reveal a negligible oxygen content for both preparation routines. Neither Fe/Ga oxides nor hydroxides were found. Both potentiostatically deposited as well as pulse deposited nanowires exhibit a preferred 〈110〉orientation, the latter with slightly larger crystals. Different contrast patterns were found by TEM that appear more pronounced in the case of pulse deposited wires. High resolution transmission electron microscopy analysis and comparison of differently prepared focused ion beam lamellas reveal that these contrasts are caused by defects in the alternating potential deposition itself and are not induced during the TEM preparation process. The alternating potential mode causes periodic growth thereby inducing different layers with reduced wire thickness/defects at the layer interfaces.

The control of magnetic properties by an electric field is exciting both from the point of view of applications and fundamental research. Low-power electrical switching of magnetic properties is e.g. discussed as promising alternative to temperature control as in heat assisted magnetic recording. Magnetoelectric coupling is known for one- or two-phase multiferroic materials and magnetic semiconductors but is, in these cases, restricted to low temperatures or a fixed substrate. More and more studies report on an influence of electric field on the magnetism also of nanostructured metals [1-6]. The advantage here is that an effect can be exploited at room temperature and may be very large due to the strong ferromagnetism. The electric field can be applied either by using solid dielectric layers or by liquid electrolytes. Many magnetic properties as e.g. coercivity, saturation magnetization, anisotropy and Curie temperature have been shown to be electric field dependent and large effects have been achieved already. Materials studied include Fe, Co, FePt, FePt, CoPt ultrathin films or nanoporous structures. In almost all cases, however, the simple picture of an increase/decrease of DOS at the metal surface is not sufficient to explain the dependencies. Enlightening the underlying mechanism requires a detailed interface analysis to understand the influence of interface chemistry, stress and strain for the distinct sample and gating architecture. The role of oxygen at the interface has been found to be crucial. Reversible potential dependent oxidation and reduction reactions as well as oxygen hybridization have been discussed as origin for magnetic property changes [2-6]. Our concept follows this argumentation and seeks to by intention exploit reversible electrochemical surface reactions involving magnetic species. This allows addressing surface magnetism by an external voltage, opening the way to controlled electrical switching of magnetic properties.

Composition and structure of electrodeposited Fe–Pt–O films are investigated in dependence on deposition potential. At potentials positive to the hydrogen evolution, a solid solution of Pt with some Fe is present that can be explained by underpotential deposition of Fe. In the potential region where hydrogen evolution by proton reduction is a side reaction, oxygen is detected in the films. The O content scales with the Fe content and at least part of the Fe is oxidized. When applying more cathodic potentials, the fraction of Fe and O increases, grain size is reduced and an amorphous/nanocrystalline phase forms. The Fe content is pH dependent in this potential region. At even more cathodic potentials, overpotential deposition of Fe in the bcc structure sets in, the O content is reduced. The results are discussed with respect to thermodynamics in the Fe–Pt–(O) system. The concepts of underpotential deposition of Fe during Fe-Pt alloy deposition and of hydroxide formation due to a pH rise at the cathode are evaluated. These simple models can only partially describe the deposition process in agreement with the compositional and structural information obtained and a coupled mechanism is proposed.

An electrochemical quartz crystal microbalance study has been performed in order to understand the alloy electrodeposition process and especially the mechanism of oxygen incorporation during Fe–Pt electrodeposition. It reveals that the presence of Pt leads to an enhanced hydrogen evolution reaction. In comparison to the single metal depositions, an additional current and an anomalous mass increase are observed when depositing from the complete electrolyte. The corresponding films exhibit a high O content and a needle-like morphology. These characteristics are altered by nitrogen gas stirring. Fe hydroxide formation due to a pH rise at the cathode and underpotential deposition of Fe deposition due to Fe–Pt alloy formation are discussed to interpret the results.

Fe(Pt)/Pt(Fe) multilayers have been prepared by single bath technique using pulse deposition under potential control. The Pt-rich layers consist of Pt fcc with some Fe substitution, and the Fe-rich layers exhibit Fe bcc structure. With this multilayer approach the oxygen incorporation, which reaches 30 at.% in homogeneous electrodeposited FePt films, can be significantly reduced. The bilayer thickness as well as the integral composition of the multilayers are adjusted by the pulse durations. Multilayers with an Fe/Pt ratio of 1.0, around 10 at.% O, and a bilayer thickness of about 40 nm are achieved. Annealing these multilayers in hydrogen atmosphere leads to intermixing, formation of the FePt L10 phase and excellent hard magnetic properties. Keywords: FePt electrodeposition, Oxygen, Multilayers, Pulse plating, Hard magnetic films

Oxides with spinel structure have received widespread attention as being suitable electrode materials for rechargeable Li-ion batteries. So far they have mostly been synthesized at relatively high temperatures of between 700 and 800 °C. Here, we describe a new synthesis route to LiMn2O4 and manganese dioxides with spinel structure based on the freeze-drying of aqueous solutions and allowing the preparation of spinels at temperatures of around 400 °C. Undoped and Bi doped samples were prepared and investigated electrochemically in strong alkaline electrolyte (9 M KOH) with regard to their charge/discharge properties. As is known from other modifications of manganese dioxides, the cyclability is improved in the presence of bismuth ions.

We describe a new chemical solution deposition (CSD) route toward inexpensive and environmentally friendly preparation of YBCO coated conductors. This route is based on a fluorine-free polymer and exhibits some advantages compared to the TFA route, where trifluoroacetate precursors are used and aggressive HF is formed during the heat treatment. In this work, the main parameters influencing the structure and properties of YBCO films prepared by means of the polymer method are investigated. For the preparation of the YBCO films, stoichiometric amounts of Y, Ba and Cu nitrates were dissolved in a solution of polyacrylic acid in dimethylformamide. This metal polymer precursor solution was spin coated onto strontium titanate (STO) single crystals. After drying in air, the films were heat treated in an oxygen containing nitrogen atmosphere. The film structure was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). T/sub c/ and J/sub c/ were measured inductively. The preliminary results show that the amount of oxygen during heating and in the dwell time strongly influences the superconducting properties. Good superconducting properties, with T/sub c/ of 89.9 K (/spl Delta/T/sub c/=1.1 K) and J/sub c/ of 10/sup 6/ A/cm/sup 2/ at 77 K, have been obtained on epitaxially grown 250-nm-thick YBCO films using the polymer-based precursors.

Co-rich Co-Pt films have been electrodeposited on Si (100) substrates with a 30 nm thick Cr buffer and a 10 nm Au conducting layer. Films have been deposited on different days after preparing the electrolyte, at current density of 28 mA/cm2, keeping all other deposition parameters constant. It has been observed from pole figures and magnetic measurements that the age of electrolyte has a significant effect on phase formation and magnetic properties of Co-Pt films. This instability in the deposition process with the age of the electrolyte is attributed to the anodic oxidation of ammonia and citrate in the presence of Co2+ ions, which has a significant influence on the deposition of cobalt based alloys. The reduction of Co2+ can be modify by two ways. First, it is possible that the nature of the complexation of Co2+ is changed because of a decomposition of ammonium citrate and formation of new compounds. Secondly, the new molecules formed in the anodic reaction may decrease the rate of reduction of Co2+ by ...

The properties of electrodeposited films subsequently annealed in H2 are reported and compared with those of vacuum-annealed samples. Annealing in hydrogen reduces the oxygen content incorporated during electrodeposition, resulting in significantly higher magnetization values. Phase formation is enhanced by hydrogen and L10 ordering starts at temperatures as low as 350°C. In addition, grain growth is hindered. These effects contribute to the high coercivity of 1.1T achieved after annealing at 600°C in H2.

FePt films of different compositions have been electrodeposited on Cu coated Si substrates. After deposition films were annealed at temperatures up to 900 °C for 10 min. Phase formation, microstructure, and magnetic properties are analyzed. From these measurements, necessary conditions to obtain good hard magnetic properties are concluded. Remanence reaches a maximum value at 800 °C annealing temperature, while coercivity continuously increases for annealing temperatures up to 900 °C. A coercivity of 0.42 T has been achieved in this case.

Iron based alloys exhibit extraordinary material and magnetic properties. They are of fundamental scientific interest, e.g. as smart and intelligent materials for magnetic storage, recording, sensing or actuating. There is an increasing importance of technical applications due to ongoing omnipresent miniaturization and integration in MEMS/NEMS systems. The dimension and geometry of the material can be tailored towards thin films, nanowires or advanced nanostructures generating high functionality for various purposes. To meet demands in miniaturization and performance of electronic devices, often low dimensional structures with highly complex geometries are requested. Electrodeposition is the most appropriate, cost and time efficient method for the fabrication of well-ordered nanoscaled structures and in particular to produce high aspect ratio nanowires. The preparation of nanoscaled magnetic materials such as Co, Fe and Ni in porous templates is a well known standard procedure [1-3]. Magnetic alloys or multilayers with specific magnetic properties are still of increasing interest. Compared to single metal deposition a more precise control of the respective electrolyte composition and deposition parameters is needed. Alloy deposition is often restrained by a strong difference in deposition potentials of the respective components. In reduced dimensions transport conditions and therefore, deposition kinetics are crucial for a successful plating process, too. This contribution focusses on the electrochemical preparation of Fe-based magnetic alloys such as Co-Fe, Fe-Ga, Fe-Pd and Fe-Pt. CoFe alloys are well known for tremendous soft magnetic properties with high saturation polarization of up to 2.4 T. A high magnetostriction is achieved in Fe-Ga alloys with 80 at.% Fe. The Fe70Pd30 alloy exhibits the magnetic shape memory effect. The Fe-Pt L10 phase shows good hard magnetic behavior due to high magnetocrystalline anisotropy and a high saturation magnetization. Therefore these alloys are very promising candidates for smart and intelligent materials in the fields of actuating or sensing or as micromagnets in MEMS. For the Co-Fe system simple sulfate based electrolytes and potentiostatic deposition [4] as well as alternating potential regimes are most efficient. The more challenging systems Fe-Ga, Fe-Pd [5, 6] and Fe-Pt require advanced complexed electrolytes. Deposition mechanisms are discussed based on quartz microbalance experiments. Deposition parameters are systematically investigated with regard to compact defect free deposits with homogeneous composition distribution. The correlation of electrolyte composition and deposition regime with deposit structure, morphology and magnetic properties is discussed. [1] Schlörb et al., Phys. Status Solidi B 247, 2010, 2463 [2] Haehnel et al., Acta Mater. 58, 2010, 2330 [3] Nielsch et al., Adv. Mater. 12, 2000, 582 [4] Vock et al., J. Appl. Phys. 118, 2015, 233901 [5] Iselt et al., J. Electrochem. Soc. 159, 2012, H633 [6] Konczak et al., Mater. Chem. Phys. 174, 2016, 150

In the present paper, the use of high aspect ratio metallic nanowires (NWs) as functional interconnects between three-dimensionally stacked chips is proposed. First practical preparation steps, as there are the preparation of templates and the deposition of Ag-NWs, are presented. Later on, the applicational technology for vertically aligned NWs is proposed as their embedment into a polymer matrix resulting in an anisotropically conductive composite film. This is discussed in both technological and functional aspects.

Ni nanowires were deposited into nanoporous alumina by pulse electrodeposition. The temperature dependent magnetic properties are analyzed in detail and a maximum of coercivity and anisotropy field is observed around room temperature which cannot simply be explained by shape anisotropy. A model is proposed which considers the competing magnetoelastic anisotropy originating from the difference in thermal expansion coefficient of the Al-substrate and the filled alumina template.

Two alternative preparation routes for FePt films are compared: pulsed laser deposition (PLD) and electrodeposition. It is described how an optimal microstructure can be obtained for best magnetic properties, and the advantages of both preparation routes are discussed. The low slope of the initial magnetization curve annealed at optimum conditions indicates that coercivity in electrodeposited granular films is controlled by pinning. In contrary, epitaxial films prepared by PLD on MgO(100) show that domain reversal in FePt films reaching the highest coercivity is governed by nucleation.

This is a co-publication with Superconductor Science and Technology. The bulk of the papers, after peer review, are published in Journal of Physics: Conference Series. However a selection of papers, are published separately in a special issue of Superconductor Science and Technology.

During the 9th European Conference on Applied Superconductivity, 6 plenary, 22 invited, 206 oral and 429 poster contributions were presented on recent developments in the field of applied superconductivity. This issue of Superconductor Science and Technology contains plenary, invited and a selection of contributed oral papers of the four main EUCAS areas: materials, wires and tapes, large scale applications and electronics. The remaining contributed papers that were selected for the conference proceedings will be published in the Journal of Physics: Conference Series. The Dresden EUCAS conference, with 712 participants from 43 countries, continued the tradition of preceding EUCAS conferences of combining basic superconductivity research contributions with the discussion of recent material advances and new developments in large scale and electronic applications. In Dresden, contributions on the recently discovered Fe-based superconductors were presented for the first time during a EUCAS conference and their potential for applications was intensively discussed. Among all the high level papers of this issue we particularly want to highlight the plenary contribution of Praveen Chaudhari on grain boundaries in cuprate superconductors. In his paper Praveen discusses the Jc limitation in HTSC tapes and tunnelling spectroscopy in LSCO thin film bicrystals. Just a few weeks ago we received the sad news that Praveen had passed away on 13 January 2010. Already fighting with his serious illness, Praveen spent all his efforts last fall finishing his plenary talk and paper. This paper will remind us always of his contributions to basic and applied aspects of superconductivity in general and especially his important work on HTSC grain boundaries. Finally we want to acknowledge the help of the International Advisory and National Committees in setting up the scientific program and we would especially like to express our gratitude to all the members of the Local Organization Committee. Their enthusiastic and well organized work made this Dresden EUCAS conference a memorable event for all participants.

We demonstrate a new approach to fabricate highly ordered arrays of nanoscopic palladium dots and wires using switchable block copolymer thin films. The surface-reconstructed block copolymer templates were directly deposited with palladium nanoparticles from a simple aqueous solution. The preferential interaction of the nanoparticles with one of the blocks is mainly responsible for the lateral arrangement of the nanoparticles inside the pores of the templates in addition to the capillary forces. A subsequent stabilization by UV-irradiation followed by pyrolysis in air at 450 degrees C removes the polymer to produce highly ordered metallic nanostructures. We extended this approach to micellar films to obtain metallic nanostructures. This method is highly versatile as the procedure used here is simple, eco-friendly and provides a simple approach to fabricate a broad range of nanoscaled architectures with tunable lateral spacing, and can be extended to systems with even smaller dimensions.

L10 FePt films with a small grain size of around 13nm have been prepared by electrodeposition and postannealing at a low annealing temperature of 400°C. A high remanence of up to 0.9T is achieved due to remanence enhancement by exchange coupling between the nanosized grains. Coercivity increases with longer annealing time as the L10 order becomes more complete. The resulting maximum energy product reaches a high value of 70kJ∕m3 after annealing for 120min, exceeding the maximum energy products so far obtained in electrodeposited hard magnetic films.