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Non-centrosymmetric superconductors have recently received significant interest due to their intriguing physical properties such as multigap and nodal superconductivity, helical vortex states, as well as non-trivial topological effects. Moreover, large values of the upper critical magnetic field have been reported in these materials. Here, we focus on the study of the temperature dependence of the perpendicular magnetic field of NbRe and NbReN films patterned in micrometric strips. The experimental data are studied within the Werthamer–Helfand–Hohenberg theory, which considers both orbital and Zeeman pair breaking. The analysis of the results shows different behavior for the two materials with a Pauli contribution relevant only in the case of NbReN.

The application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction, named as gate-controlled supercurrent (GCS), has raised great interest for fundamental and technological reasons. To gain a deeper understanding of this effect and develop superconducting technologies based on it, the material and physical parameters crucial for the GCS effect must be identified. Top-down fabrication protocols should also be optimized to increase device scalability, although studies suggest that top-down fabricated devices are more resilient to show a GCS. Here, we investigate gated superconducting nanobridges made with a top-down fabrication process from thin films of the non-centrosymmetric superconductor niobium rhenium with varying ratios of the constituents (NbRe). Unlike other devices previously reported and made with a top-down approach, our NbRe devices systematically exhibit a GCS effect when they were fabricated from NbRe thin films with small grain size and etched in specific conditions. These observations pave the way for the realization of top-down-made GCS devices with high scalability. Our results also imply that physical parameters like structural disorder and surface physical properties of the nanobridges, which can be in turn modified by the fabrication process, are crucial for a GCS observation, providing therefore also important insights into the physics underlying the GCS effect.

ZnO nanoparticles were synthesised by a one-step mechanochemical process using ZnSO4 and NaOH as reactants with NaCl acting as a diluent. A short milling time of 30 min was required for complete reaction. The effects of oxygen vacancies and the milling time on the photocatalytic activities of the prepared nanoparticles were investigated. The structural and morphological properties of the nanoparticles were evaluated by various analytical methods, including x-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The particle size of the ZnO nanoparticles without heat treatment was approximately 50 nm but was increased up to 80 nm after heat treatment at 400 degrees Celsius. Optical properties such as the optical band gap and the photocatalytic activity were investigated, by photoluminescence and UV-vis spectroscopy, as well as by photocatalytic experiments.

Zinc oxide (ZnO) nanoparticles were synthesised by a mechanochemical method using ZnCl2 and Na2CO3 as precursors and NaCl as a diluent. The effects of the milling energy, influenced by factors such as the milling time and ball-to-powder mass ratio, and the ordering of the synthetic stages on the structure, morphology and optical properties of the synthesised nanoparticles were characterised by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, as well as by UV-visible and photoluminescence spectroscopies. The results indicated the direct formation of ZnO nanoparticles after 10 hours of milling, without the need for heat treatment, as a result of the high-energy milling process. The crystallite sizes of the nanoparticles increased with higher milling times and ball-to powder mass ratios due to cold welding. ZnO nanoparticles with crystallite sizes in the range of 16 nm-19 nm were produced, through optimisation of the order of synthetic stages and milling energy.

The application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction, named as gate-controlled supercurrent (GCS), has raised great interest for fundamental and technological reasons. To gain a deeper understanding of this effect and develop superconducting technologies based on it, the material and physical parameters crucial for GCS must be identified. Top-down fabrication protocols should be also optimized to increase device scalability, although studies suggest that top-down fabricated devices are more resilient to show GCS. Here, we investigate gated superconducting nanobridges made with a top-down fabrication process from thin films of the non-centrosymmetric superconductor NbRe. Unlike other devices previously reported, our NbRe devices systematically exhibit GCS, when made in specific conditions, which paves the way for higher device scalability. Our results also suggest that surface properties of NbRe nanobridges and their modification during fabrication are key for GCS.