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An ultra-fast method to directly grow metallic micro- and nano-structures is introduced. It relies on a Focused Ion Beam (FIB) and a condensed layer of suitable precursor material formed on the substrate under cryogenic conditions. The technique implies cooling the substrate below the condensation temperature of the gaseous precursor material, subsequently irradiating with ions according to the wanted pattern, and posteriorly heating the substrate above the condensation temperature. Here, using W(CO)6 as the precursor material, a Ga+ FIB, and a substrate temperature of -100 °C, W-C metallic layers and nanowires with resolution down to 38 nm have been grown by Cryogenic Focused Ion Beam Induced Deposition (Cryo-FIBID). The most important advantages of Cryo-FIBID are the fast growth rate (about 600 times higher than conventional FIBID with the precursor material in gas phase) and the low ion irradiation dose required (∼50 μC/cm2), which gives rise to very low Ga concentrations in the grown material and in the substrate (≤0.2%). Electrical measurements indicate that W-C layers and nanowires grown by Cryo-FIBID exhibit metallic resistivity. These features pave the way for the use of Cryo-FIBID in various applications in micro- and nano-lithography such as circuit editing, photomask repair, hard masks, and the growth of nanowires and contacts. As a proof of concept, we show the use of Cryo-FIBID to grow metallic contacts on a Pt-C nanowire and investigate its transport properties. The contacts have been grown in less than one minute, which is considerably faster than the time needed to grow the same contacts with conventional FIBID, around 10 hours., Authors acknowledge financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) through the projects MAT2017-82970-C1 and MAT2017-82970-C2, from CSIC through the project PIE201760E027 and from the Aragon Regional Government (Construyendo Europa desde Aragón) through projects E13_17R and LMP33_18, with European Social Fund funding. R. C. acknowledges Juan de la Cierva Incorporación 2014 program. S. S. acknowledges the support of an Erasmus+ scholarship to fund his stay at University of Zaragoza from J. W. Goethe-Universität, Frankfurt am Main, Germany.

Under high-enough values of perpendicularly-applied magnetic feld and current, a type-II superconductor presents a fnite resistance caused by the vortex motion driven by the Lorentz force. To recover the dissipation-free conduction state, strategies for minimizing vortex motion have been intensely studied in the last decades. However, the non-local vortex motion, arising in areas depleted of current, has been scarcely investigated despite its potential application for logic devices. Here, we propose a route to transfer vortices carried by non-local motion through long distances (up to 10 micrometers) in 50nm-wide superconducting WC nanowires grown by Ga+ Focused Ion Beam Induced Deposition. A giant non-local electrical resistance of 36Ω has been measured at 2K in 3μm-long nanowires, which is 40 times higher than signals reported for wider wires of other superconductors. This giant efect is accounted for by the existence of a strong edge confnement potential that hampers transversal vortex displacements, allowing the long-range coherent displacement of a single vortex row along the superconducting channel. Experimental results are in good agreement with numerical simulations of vortex dynamics based on the time-dependent Ginzburg-Landau equations. Our results pave the way for future developments on information technologies built upon single vortex manipulation in nano-superconductors., Tis work was supported by the fnancial support from Spanish Ministry of Economy and Competitiveness through the projects MAT2015-69725-REDT, MAT2017-82970-C2-1-R and MAT2017-82970-C2-2-R, PIE201760E027, including FEDER funding, FIS2017-84330-R, MDM-2014-0377, FIS2016-80434-P and the Fundación Ramón Areces, EU ERC (Grant Agreement No. 679080), COST Grant No. CA16128 and STSM Grant from COST Action CA16218, and from regional Gobierno de Aragón (grants E13_17R and E28_17R) with European Social Fund (Construyendo Europa desde Aragón) and Comunidad de Madrid through project Nanofrontmag-CM (Grant No. S2013/MIT-2850). R.C. acknowledges Juan de la Cierva-Incorporación 2014 program.

Novel schemes based on the design of complex three-dimensional (3D) nanoscale architectures are required for the development of the next generation of advanced electronic components. He+ focused-ion-beam (FIB) microscopy in combination with a precursor gas allows one to fabricate 3D nanostructures with an extreme resolution and a considerably higher aspect ratio than FIB-based methods, such as Ga+ FIB-induced deposition, or other additive manufacturing technologies. In this work, we report the fabrication of 3D tungsten carbide nanohelices with on-demand geometries via controlling key deposition parameters. Our results show the smallest and highest-densely packed nanohelix ever fabricated so far, with dimensions of 100 nm in diameter and aspect ratio up to 65. These nanohelices become superconducting at 7 K and show a large critical magnetic field and critical current density. In addition, given its helical 3D geometry, fingerprints of vortex and phase-slip patterns are experimentally identified and supported by numerical simulations based on the time-dependent Ginzburg–Landau equation. These results can be understood by the helical geometry that induces specific superconducting properties and paves the way for future electronic components, such as sensors, energy storage elements, and nanoantennas, based on 3D compact nanosuperconductors., This work was supported by the financial support from Spanish Ministry of Economy and Competitiveness through the projects MAT2017-82970-C2-2-R, PIE201760E027, including FEDER funding, FIS2017-84330-R, MDM-2014-0377, EU ERC (grant agreement no. 679080), COST grant no. CA16128, and STSM grant 41199 for V.M.F. from COST Action CA16218, from the EU-H2020 research and innovation programme under grant agreement no. 654360 NFFA-Europe, from regional Gobierno de Aragon (grants E13_17R) with European Social Fund (Construyendo Europa desde Aragon) and Comunidad de Madrid through project Nanofrontmag-CM (grant no. S2013/ MIT-2850). Authors acknowledge the LMA-INA for offering access to their instruments and expertise and the use of Servicio General de Apoyo a la Investigacion-SAI, Universidad de Zaragoza, particularly the Servicio de Medidas Fisicas. The support of the German Research Foundation (DFG) via grant FO 956/5-1 is gratefully acknowledged. Authors acknowledge the Center for Information Services and High Performance Computing (ZIH) at TU Dresden for offering access to the HPC system. This work was supported by HFML-RU/NWO-I, member of the European Magnetic Field Laboratory (EMFL). It is part of the research program no. 132 “High Field Magnet Laboratory: a global player in science in high magnetic fields” financed by The Netherlands Organisation for Scientific Research (NWO).