3,416 research outputs found

    The Origins of the German Corporation – Finance, Ownership and Control

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    The ownership of German corporations is quite different today from that of Anglo-American firms. How did this come about? To what extent is it attributable to regulation? A specially constructed data set on financing and ownership of German corporations from the end of the 19th century reveals that, as in the UK, there was a high degree of activity on German stock markets with firms issuing equity in preference to borrowing from banks, and insider and family ownership declining rapidly. However, unlike in the UK, other companies and banks emerged as the main holders of equity, with banks holding shares primarily as custodians of other investors rather than on their own account. The changing pattern of ownership concentration was therefore very different from that of the UK with regulation reinforcing the control that banks exercised on behalf of other investors

    The Origins of the German Corporation – Finance, Ownership and Control

    Get PDF
    The ownership of German corporations is quite different today from that of Anglo-American firms. How did this come about? To what extent is it attributable to regulation? A specially constructed data set on financing and ownership of German corporations from the end of the 19th century reveals that, as in the UK, there was a high degree of activity on German stock markets with firms issuing equity in preference to borrowing from banks, and insider and family ownership declining rapidly. However, unlike in the UK, other companies and banks emerged as the main holders of equity, with banks holding shares primarily as custodians of other investors rather than on their own account. The changing pattern of ownership concentration was therefore very different from that of the UK with regulation reinforcing the control that banks exercised on behalf of other investors.Evolution of ownership; German stock markets; financial regulation

    Creating stable Floquet-Weyl semimetals by laser-driving of 3D Dirac materials

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    Tuning and stabilising topological states, such as Weyl semimetals, Dirac semimetals, or topological insulators, is emerging as one of the major topics in materials science. Periodic driving of many-body systems offers a platform to design Floquet states of matter with tunable electronic properties on ultrafast time scales. Here we show by first principles calculations how femtosecond laser pulses with circularly polarised light can be used to switch between Weyl semimetal, Dirac semimetal, and topological insulator states in a prototypical 3D Dirac material, Na3_3Bi. Our findings are general and apply to any 3D Dirac semimetal. We discuss the concept of time-dependent bands and steering of Floquet-Weyl points (Floquet-WPs), and demonstrate how light can enhance topological protection against lattice perturbations. Our work has potential practical implications for the ultrafast switching of materials properties, like optical band gaps or anomalous magnetoresistance. Moreover, we introduce Floquet time-dependent density functional theory (Floquet-TDDFT) as a general and robust first principles method for predictive Floquet engineering of topological states of matter.Comment: 21 pages, 4 figure

    The effect of confinement and defects on the thermal stability of skyrmions

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    The stability of magnetic skyrmions against thermal fluctuations and external perturbations is investigated within the framework of harmonic transition state theory for magnetic degrees of freedom. The influence of confined geometry and atomic scale non-magnetic defects on the skyrmion lifetime is estimated. It is shown that a skyrmion on a track has lower activation energy for annihilation and higher energy for nucleation if the size of the skyrmion is comparable with the width of the track. Two mechanisms of skyrmion annihilation are considered: inside the track and escape through the boundary. For both mechanisms, the dependence of activation energy on the track width is calculated. Non-magnetic defects are found to localize skyrmions in their neighborhood and strongly decrease the activation energy for creation and annihilation. This is in agreement with experimental measurements that have found nucleation of skyrmions in presence of spin-polarized current preferably occurring near structural defects
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