Control of tetrahedral coordination and superconductivity in FeSe0.5Te0.5 thin films

We demonstrate a close relationship between superconductivity and the dimensions of the Fe-Se(Te) tetrahedron in FeSe0.5Te0.5. This is done by exploiting thin film epitaxy, which provides controlled biaxial stress, both compressive and tensile, to distort the tetrahedron. The Se/Te height within the tetrahedron is found to be of crucial importance to superconductivity, in agreement with the theoretical proposal that (pi,pi) spin fluctuations promote superconductivity in Fe superconductors

Antisymmetric magnetoresistance in magnetic multilayers with perpendicular anisotropy

While magnetoresistance (MR) has generally been found to be symmetric in applied field in non-magnetic or magnetic metals, we have observed antisymmetric MR in Co/Pt multilayers. Simultaneous domain imaging and transport measurements show that the antisymmetric MR is due to the appearance of domain walls that run perpendicular to both the magnetization and the current, a geometry existing only in materials with perpendicular magnetic anisotropy. As a result, the extraordinary Hall effect (EHE) gives rise to circulating currents in the vicinity of the domain walls that contributes to the MR. The antisymmetric MR and EHE have been quantitatively accounted for by a theoretical model.Comment: 17 pages, 4 figure

Predicting the ‘Unpredictable’ General Anti-Avoidance Rule (GAAR) in EU Tax Law

General Anti-Avoidance Rule (GAAR) is a type of rule designed to combat the tax-avoidance scenarios that in a legal form lawfully but aims to circumvent the legal consequences. GAAR is necessary for a tax system to address unexpected innovative tax avoidance scenarios. In the field of tax law, GAAR has been criticized for being too abstract and thus harmful to legal certainty. In the context of EU integration, the concept of GAAR has been developed and elaborated by Court of Justice of European Union as well as secondary laws, but there are quite a few different formulations. In the existing literature, it is established that, there are the subject test and the objective test cumulatively in the GAAR, which examines the taxpayers’ subjective intension and the objective economic reality. As to the relation between these two tests, scholars have established the theory that, the formulation and the context of the subjective test is actually influenced by the tax rule involved (that is, the purpose of the norm being circumvented). This paper will revisit GAARs in the EU tax law and present that, the theory of GAAR based on the purpose of the violated tax norm is indeed supported by latest case law of CJEU as well new Directives. Furthermore, the intention of the norm reconciles the subject test and the objective test. In this regard, the unpredictability of ‘GAAR’ actually has become more predictable

Continuation-minimization methods for stability problems

AbstractWe study the solution branches of stable and unstable bifurcations in certain semilinear elliptic eigenvalue problems with Dirichlet boundary conditions. A secant predictor-line search backtrack corrector continuation method is described to trace the solution curves numerically. Sample numerical results with computer graphic output are reported