Simultaneous control of magnetic topologies for reconfigurable vortex arrays

The topological spin textures in magnetic vortices in confined magnetic elements offer a platform for understanding the fundamental physics of nanoscale spin behavior and the potential of harnessing their unique spin structures for advanced magnetic technologies. For magnetic vortices to be practical, an effective reconfigurability of the two topologies of magnetic vortices, that is, the circularity and the polarity, is an essential prerequisite. The reconfiguration issue is highly relevant to the question of whether both circularity and polarity are reliably and efficiently controllable. In this work, we report the first direct observation of simultaneous control of both circularity and polarity by the sole application of an in-plane magnetic field to arrays of asymmetrically shaped permalloy disks. Our investigation demonstrates that a high degree of reliability for control of both topologies can be achieved by tailoring the geometry of the disk arrays. We also propose a new approach to control the vortex structures by manipulating the effect of the stray field on the dynamics of vortex creation. The current study is expected to facilitate complete and effective reconfiguration of magnetic vortex structures, thereby enhancing the prospects for technological applications of magnetic vortices.ope

Bail-In from an Insolvency Law Perspective

Coherent privaatrech

Stochastic formation of magnetic vortex structures in asymmetric disks triggered by chaotic dynamics

The non-trivial spin configuration in a magnetic vortex is a prototype for fundamental studies of nanoscale spin behaviour with potential applications in magnetic information technologies. Arrays of magnetic vortices interfacing with perpendicular thin films have recently been proposed as enabler for skyrmionic structures at room temperature, which has opened exciting perspectives on practical applications of skyrmions. An important milestone for achieving not only such skyrmion materials but also general applications of magnetic vortices is a reliable control of vortex structures. However, controlling magnetic processes is hampered by stochastic behaviour, which is associated with thermal fluctuations in general. Here we show that the dynamics in the initial stages of vortex formation on an ultrafast timescale plays a dominating role for the stochastic behaviour observed at steady state. Our results show that the intrinsic stochastic nature of vortex creation can be controlled by adjusting the interdisk distance in asymmetric disk arrays.close31

Corporate Governance, Capital Market Regulation and the Challenge of Disembedded Markets

Long before the current financial and economic crisis, corporate governance and securities regulation had become part of one of the most interesting and dynamic regulatory areas in law and policy making today. Both areas had been undergoing dramatic transformations over the past 30-40 years, which saw a global expansion of capital markets and a deep-running ‘financialisation’ of the corporation. Around the world governments saw themselves challenged to adapt their regulatory apparatus to the whims and hues of nervous investors with global sensitivities. Meanwhile, scholars in law, economics, but also political science and sociology fiercely debated whether what was unfolding constituted a worldwide convergence around a corporate governance philosophy that placed the shareholder at the centre or whether we would continue to have different, divergent corporate governance systems around the world. Today’s crisis-responses appear to be primarily designed to ‘fix the excesses’ of the past decades, rather than driven by an interest to connect the present efforts at regulation with the earlier convergence vs. divergence debates, which themselves built on much older critiques of the embeddedness of the firm and the political economy context of corporate activity. The paper contends that the sustainability of future corporate governance and securities regulation depends on the effort to critically examine both areas in the context of a larger inquiry into the goals and challenges of market regulation