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Co 1 − x Pt x nanowire arrays embedded in anodic aluminum oxide templates were fabricated by an electrochemical route. X-ray magnetic circular dichroism (XMCD) measurements were conducted at the Co L2,3 edges on samples with an array of nanowire bundles at the substrate surfaces. The ratios between the orbital and the spin moments R were estimated to be about 0.19 (±0.03) and 0.07 (±0.03) for 20nm Co and 14nm Co91Pt9 nanowires, respectively. A strong temperature dependence of the R value was observed. The x-ray absorption spectra also indicated the presence of CoO, which did not contribute to the XMCD signals.

A high resolution soft x-ray photoelectron spectroscopic study of Ga and As 3d core levels has been conducted for Fe/GaAs (001) as a function of Fe thickness.This work has provided unambiguous evidence of substrate disrupting chemical reactions induced by the Fe overlayer -a quantitative analysis of the acquired spectra indicates significantly differing behaviour of Ga and As during Fe growth, and our * Corresponding author, e-mail: t.shen@salford.ac.uk 2 observations have been compared with existing theoretical models. Our results demonstrate that the outdiffusing Ga and As remain largely confined to the interface region, forming a thin intermixed layer. Whereas at low coverages Fe has little influence on the underlying GaAs substrate, the onset of substrate disruption when the Fe thickness reaches 3.5 Å results in major changes in the energy distribution curves (EDCs) of both As and Ga 3d cores. Our quantitative analysis suggests the presence of two new As environments of metallic character; one bound to the interfacial region and another which, as confirmed by in-situ oxidation experiments, surface segregates and persists over a wide range of overlayer thickness. Analysis of the corresponding Ga 3d EDCs found not two, but three new environments -also metallic in nature.

The elastic response of BaTiO3 single crystals during electric field cycling at room temperature has been studied using in-situ Resonant Ultrasound Spectroscopy (RUS), which allows monitoring of both the elastic and anelastic changes caused by ferroelectric polarization switching. We find that the first ferroelectric switching of a virgin single crystal is dominated by ferroelastic 90° switching. In subsequent ferroelectric switching, ferroelastic switching is reduced by domain pinning and by the predominance of 180° ferroelectric domains, as confirmed by polarized light microscopy. RUS under in-situ electric field therefore demonstrates to be an effective technique for the investigation of electromechanical coupling in ferroelectrics.The process of polarization switching in ferroelectrics is generally not homogeneous and involves nucleation and growth of domains [1,2]. In prototypical tetragonal ferroelectrics, such as BaTiO3 at room temperature, two kinds of ferroelectric domains can nucleate [3]: 180° domains with polarizations antiparallel to each other, which minimize depolarization fields, and 90° domains with polarizations orthogonal to each other, which minimize strain via the formation of twins. During electrical poling, local strains are generated when 90° domains switch, but not when 180° domains switch. Limiting the mobility of domain walls by introducing specific point defects and domain engineering has proven an effective strategy to enhance piezoelectricity in BaTiO3 [4,5]. Large strains are desirable, e.g., to achieve giant magnetoelectric effects in multiferroic composites [6][7][8][9][10], and polarization switching without domain propagation is preferred for ferroelectric memory devices [11,12]. Separately, domain wall pinning and domain jamming may cause fatigue effects in ferroelectrics, hampering polarization switching upon repeated voltage cycling, ultimately limiting the performance of devices [13,14]. Understanding the role of domain structure on ferroelectric switching is thus of high technological relevance for the optimization

Isotopic analyses of prehistoric diet have only recently reached the threshold of going beyond site-focused reports to provide regional syntheses showing larger trends. In this work we present the first regional analysis for Neolithic southeastern Italy as a whole, including both substantial original data and a review of the available published data. The results show that dietary isotopes can shed new light on a number of traditional and important questions about Neolithic foodways. First, we observe regional variations in the distribution of stable isotope values across the area, suggesting variability in the Neolithic diet. Secondly, we show that, although the plant food calorific intake was primary for these communities, animal products were also important, representing on average 40% of the total calories. Third, we note that marine fish was only minorly consumed, but that this could be an underestimation, and we observe some variability in the regions considered, suggesting differences in local human–environment interactions. People in different regions of southeastern Italy may have consumed different versions of a common Neolithic diet. Regional synthesis also allows us to take stock of gaps and new directions in the field, suggesting an agenda for Neolithic isotopic research for the 2020s.