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The chemical bath deposition (CBD) process enables the deposition of ZnO nanowires (NWs) on various substrates with customizable morphology. However, the hydrogen-rich CBD environment introduces numerous hydrogen-related defects, unintentionally doping the ZnO NWs and increasing their electrical conductivity. The oxygen-based plasma treatment can modify the nature and amount of these defects, potentially tailoring the ZnO NW properties for specific applications. This study examines the impact of the average ion energy on the formation of oxygen vacancies (VO) and hydrogen-related defects in ZnO NWs exposed to low-pressure oxygen plasma. Using X-ray photoelectron spectroscopy (XPS), 5 K cathodoluminescence (5K CL), and Raman spectroscopy, a comprehensive understanding of the effect of the oxygen ion energy on the formation of defects and defect complexes was established. A series of associative and dissociative reactions indicated that controlling plasma process parameters, particularly ion energy, is crucial. The XPS data suggested that increasing the ion energy could enhance Fermi level pinning by increasing the amount of VO and favoring the hydroxyl group adsorption, expanding the depletion region of charge carriers. The 5K CL and Raman spectroscopy further demonstrated the potential to adjust the ZnO NW physical properties by varying the oxygen ion energy, affecting various donor- and acceptor-type defect complexes. This study highlights the ability to tune the ZnO NW properties at low temperature by modifying plasma process parameters, offering new possibilities for a wide variety of nanoscale engineering devices fabricated on flexible and/or transparent substrates.

We measured the radiation tolerance of commercially available diamonds grown by the Chemical Vapor Deposition process by measuring the charge created by a 120 GeV hadron beam in a 50 μm pitch strip detector fabricated on each diamond sample before and after irradiation. We irradiated one group of samples with 70 MeV protons, a second group of samples with fast reactor neutrons (defined as energy greater than 0.1 MeV), and a third group of samples with 200 MeV pions, in steps, to (8.8±0.9) × 1015 protons/cm2, (1.43±0.14) × 1016 neutrons/cm2, and (6.5±1.4) × 1014 pions/cm2, respectively. By observing the charge induced due to the separation of electron–hole pairs created by the passage of the hadron beam through each sample, on an event-by-event basis, as a function of irradiation fluence, we conclude all datasets can be described by a first-order damage equation and independently calculate the damage constant for 70 MeV protons, fast reactor neutrons, and 200 MeV pions. We find the damage constant for diamond irradiated with 70 MeV protons to be 1.62±0.07(stat)±0.16(syst)× 10−18 cm2/(p μm), the damage constant for diamond irradiated with fast reactor neutrons to be 2.65±0.13(stat)±0.18(syst)× 10−18 cm2/(n μm), and the damage constant for diamond irradiated with 200 MeV pions to be 2.0±0.2(stat)±0.5(syst)× 10−18 cm2/(π μm). The damage constants from this measurement were analyzed together with our previously published 24 GeV proton irradiation and 800 MeV proton irradiation damage constant data to derive the first comprehensive set of relative damage constants for Chemical Vapor Deposition diamond. We find 70 MeV protons are 2.60 ± 0.29 times more damaging than 24 GeV protons, fast reactor neutrons are 4.3 ± 0.4 times more damaging than 24 GeV protons, and 200 MeV pions are 3.2 ± 0.8 more damaging than 24 GeV protons. We also observe the measured data can be described by a universal damage curve for all proton, neutron, and pion irradiations we performed of Chemical Vapor Deposition diamond. Finally, we confirm the spatial uniformity of the collected charge increases with fluence for polycrystalline Chemical Vapor Deposition diamond, and this effect can also be described by a universal curve.

The performance of thermoelectric (TE) modules is governed not only by the thermoelectric materials whose properties are capitalized, but also on the quality of the electrical contacts which are ubiquitous in the design of the device. To ensure the necessary stability of the interfaces between the TE materials and the electrodes, diffusion barriers are generally used. In this study, attempts are presented in finding diffusion barriers that would be suitable for Mg2(Si,Ge) TE materials. These involved the deposition by microwave plasma-assisted co-sputtering of intermediate gradient layers starting from Mg and Si, ending up with a Ni layer, or the deposition of metallic layers (Ti, Cr, W and Ta). The effectiveness of the deposited layers as diffusion barriers is assessed after the legs were subjected to a brazing process, with the results favoring the use of gradient layers with a thick Ni layer and metallic layers based on Ta and Cr, despite some adherence issues for the latter.

We measured the radiation tolerance of commercially available diamonds grown by the Chemical Vapor Deposition process by measuring the charge created by a 120 GeV hadron beam in a 50 μm pitch strip detector fabricated on each diamond sample before and after irradiation. We irradiated one group of samples with 70 MeV protons, a second group of samples with fast reactor neutrons (defined as energy greater than 0.1 MeV), and a third group of samples with 200 MeV pions, in steps, to (8.8±0.9) × 1015 protons/cm2, (1.43 ± 0.14) × 1016 neutrons/cm2, and (6.5 ± 1.4) × 1014 pions/cm2, respectively. By observing the charge induced due to the separation of electron–hole pairs created by the passage of the hadron beam through each sample, on an event-by-event basis, as a function of irradiation fluence, we conclude all datasets can be described by a first-order damage equation and independently calculate the damage constant for 70 MeV protons, fast reactor neutrons, and 200 MeV pions. We find the damage constant for diamond irradiated with 70 MeV protons to be 1.62 ± 0.07(stat) ± 0.16(syst) × 10–18 cm2/(p μm), the damage constant for diamond irradiated with fast reactor neutrons to be 2.65 ± 0.13(stat) ± 0.18(syst) × 10–18 cm2/(n μm), and the damage constant for diamond irradiated with 200 MeV pions to be 2.0 ± 0.2(stat) ± 0.5(syst) × 10–18 cm2/(π μm). The damage constants from this measurement were analyzed together with our previously published 24 GeV proton irradiation and 800 MeV proton irradiation damage constant data to derive the first comprehensive set of relative damage constants for Chemical Vapor Deposition diamond. We find 70 MeV protons are 2.60 ± 0.29 times more damaging than 24 GeV protons, fast reactor neutrons are 4.3 ± 0.4 times more damaging than 24 GeV protons, and 200 MeV pions are 3.2 ± 0.8 more damaging than 24 GeV protons. We also observe the measured data can be described by a universal damage curve for all proton, neutron, and pion irradiations we performed of Chemical Vapor Deposition diamond. Finally, we confirm the spatial uniformity of the collected charge increases with fluence for polycrystalline Chemical Vapor Deposition diamond, and this effect can also be described by a universal curve.

The performance of thermoelectric (TE) modules is governed not only by the thermoelectric materials whose properties are capitalized, but also on the quality of the electrical contacts which are ubiquitous in the design of the device. To ensure the necessary stability of the interfaces between the TE materials and the electrodes, diffusion barriers are generally used. In this study, attempts are presented in finding diffusion barriers that would be suitable for Mg 2 (Si,Ge) TE materials. These involved the deposition by microwave plasma-assisted co-sputtering of intermediate gradient layers starting from Mg and Si, ending up with a Ni layer, or the deposition of metallic layers (Ti, Cr, W and Ta). The effectiveness of the deposited layers as diffusion barriers is assessed after the legs were subjected to a brazing process, with the results favoring the use of gradient layers with a thick Ni layer and metallic layers based on Ta and Cr, despite some adherence issues for the latter.

1.8 micrometer-thick magnesium hydride films were synthesized in a single-step process by reactive plasma-assisted sputtering. The MgH2 thin films, which were deposited on two types of flexible surfaces (namely graphite and polyimide foils) were found to adhere on both substrates. In all cases, XRD analysis revealed an as-deposited thin film consisting of alpha-MgH2, a tetragonal, rutile-type crystal structure (space group \\#136). The hydrogen sorption capacities of the uncapped films were studied over successive desorption/absorption cycles performed at 350 {\\textdegree}C. The first desorption always shows a slow kinetics that can be explained by a superficial oxidation of the films. However, once the passivating layer is removed, the following dehydrogenations occur faster. Multiple cycling of the film deposited on polyimide resulted in delamination of the film and its conversion into loose powder. As for MgH2 deposited on the flexible graphite substrate, a fully reversible capacity was observed over 28 cycles with no delamination of the film. Upon cycling, the microstructure of the film has evolved from homogeneous fibrous to an untextured morphology with a higher degree of crystallinity.

We report on the development of a 10B conversion layer optimized for ultra-cold neutron detection with silicon detectors. The efficiency of this layer is high and roughly uniform over a large ultra-cold neutron velocity range. The designed titanium-boron-nickel multilayer film was deposited on silicon using a microwave plasma-assisted co-sputtering method (first, for test purpose, on silicon wafers, then directly on the surface of a CCD sensor). The obtained sensor was then tested using both cold and ultra-cold neutrons.

In the context of online ion range verification in particle therapy, the CLaRyS collaboration is developing Prompt-Gamma (PG) detection systems. The originality in the CLaRyS approach is to use a beam-tagging hodoscope in coincidence with the gamma detectors to provide both temporal and spatial information of the incoming ions. The ion range sensitivity of such PG detection systems could be improved by detecting single ions with a 100 ps (\\(\\sigma\\)) time resolution, through a quality assurance procedure at low beam intensity at the beginning of the treatment session. This work presents the investigations led to assess the performance of Chemical Vapor Deposition (CVD) diamond detectors to fulfill these requirements. A \\(^{90}\\)Sr beta source, 68 MeV protons, 95 MeV/u carbon ions and a synchrotron X-ray pulsed beam were used to measure the time resolution, single ion detection efficiency and proton counting capability of various CVD diamond samples. An offline technique, based on double-sided readout with fast current preamplifiers and used to improve the signal-to-noise ratio, is also presented. The different tests highlighted Time-Of-Flight resolutions ranging from 13 ps (\\(\\sigma\\)) to 250 ps (\\(\\sigma\\)), depending on the experimental conditions. The single 68 MeV proton detection efficiency of various large area polycrystalline (pCVD) samples was measured to be \\(>\\)96% using coincidence measurements with a single-crystal reference detector. Single-crystal CVD (sCVD) diamond proved to be able to count a discrete number of simultaneous protons while it was not achievable with a polycrystalline sample. Considering the results of the present study, two diamond hodoscope demonstrators are under development: one based on sCVD, and one of larger size based on pCVD. They will be used for the purpose of single ion as well as ion bunches detection, either at reduced or clinical beam intensities.

During sex, male arousal builds to the ejaculatory threshold, allowing genital sensory input to trigger ejaculation. While copulation and arousal are thought to be brain-regulated, ejaculation is a reflex controlled by a spinal circuit. In this framework, the spinal cord is assumed to be strongly inhibited by descending input until the ejaculatory threshold, playing no role in the regulation of copulatory behavior. However, this remains untested. Here we mapped the spinal circuit controlling the bulbospongiosus muscle, essential for sperm expulsion in mice. Our findings show that bulbospongiosus muscle-motor neurons receive input from galanin-expressing neurons, which integrate genital sensory signals. Stimulating these neurons induces bulbospongiosus activity, but responses vary with spinalization, internal state, and decrease with repeated stimulation. Ablating galanin-positive neurons altered ejaculation latency and copulatory patterns. These results suggest that spinal circuits influence not only ejaculation but also copulation and arousal, challenging the traditional view of spinal control in copulation. The precise role of the spinal cord in copulatory behavior remains not fully understood. Here, authors identify a population of spinal galanin-expressing neurons that regulate sexual arousal and mating in male mice, revealing a broader role for spinal circuits in copulation than previously acknowledged.