Towards engineering the perfect defect in high-performing permanent magnets

Permanent magnets draw their properties from a complex interplay, across multiple length scales, of the composition and distribution of their constituting phases, that act as building blocks, each with their associated intrinsic properties. Gaining a fundamental understanding of these interactions is hence key to decipher the origins of their magnetic performance and facilitate the engineering of better-performing magnets, through unlocking the design of the "perfect defects" for ultimate pinning of magnetic domains. Here, we deployed advanced multiscale microscopy and microanalysis on a bulk Sm2(CoFeCuZr)17 pinning-type high-performance magnet with outstanding thermal and chemical stability. Making use of regions with different chemical compositions, we showcase how both a change in the composition and distribution of copper, along with the atomic arrangements enforce the pinning of magnetic domains, as imaged by nanoscale magnetic induction mapping. Micromagnetic simulations bridge the scales to provide an understanding of how these peculiarities of micro- and nanostructure change the hard magnetic behaviour of Sm2(CoFeCuZr)17 magnets. Unveiling the origins of the reduced coercivity allows us to propose an atomic-scale defect and chemistry manipulation strategy to define ways toward future hard magnets

Stories from the field:Women's networking as gender capital in entrepreneurial ecosystems

Women are underrepresented in successful entrepreneurial ecosystems and the creation of women-only entrepreneurial networks has been a widespread policy response. We examine the entrepreneurial ecosystem construct and suggest that it, and the role networks play in entrepreneurial ecosystems, can be analysed in terms of Bourdieu's socio-analysis as field, habitus and capital. Specifically, we develop the notion of gender capital as the skill set associated with femininity or from simply being recognized as feminine. We apply this to the development of women's entrepreneurial networks as a gender capital enhancing initiative. Using data from qualitative interviews with network coordinators and women entrepreneurs we reflect on the extent to which formally established women-only networks generate gender capital for their members and improve their ability to participate in the entrepreneurial ecosystem. The paper concludes by drawing out the implications of our analysis for theory, entrepreneurial practice and economic development policy

Transport properties of Bi2Sr2Ca2Cu3O10+δ Bicrystal Grain Boundary Josephson Junctions and SQUIDs

Josephson junctions and SQUIDs on 36.8° SrTiO3 bicrystal substrates were prepared from epitaxial Bi2Sr2Ca2Cu3O10+δ thin films with critical temperatures around 95K. The current-voltage characteristics are well described by the resistively and capacitively shunted junction model. IcRn products of 50µV at 77K and 0.7mV at 4.2K have been reached. The Ic(B) dependence is symmetric to B = 0 with an Ic suppression of 90% in the first minimum. Nevertheless it turns out, that the junctions are inhomogeneous on a µm scale. SQUID modulations observed at 78K indicate a flux-voltage transfer function of 2.7µV/Φ0 at this temperature