The impact of taxes on competition for CEOs

This paper tries to answer the question how taxation of corporate and individual income affects competition among firms for highly-skilled human resources like CEOs. It shows that individual income taxes can perform a substantial impact on the outcome of such a competition if marginal tax rates are different like in an international labor market. Additionally, it presents the surprising result that in a local labor market for CEOs observed gross fixed salaries should decline in the individual income tax rate. The effects of taxation in a market for CEOs is in particular an interesting topic because recent developments with respect to compensation practices of top-level managers have opened a public debate about the use of instruments for regulating compensation of those managers. The investigation follows an analytical economics-based approach by extending an LEN type model of moral hazard with elements of competition and income taxation. It investigates the impact of differential taxation on the competition between two firms for the exclusive service of a unique, highly-skilled CEO

Microwave cavity-enhanced transduction for plug and play nanomechanics at room temperature

Nanomechanical resonators with increasingly high quality factors are enabled following recent insights into energy storage and loss mechanisms in nanoelectromechanical systems (NEMS). Consequently, efficient, non-dissipative transduction schemes are required to avoid the dominating influence of coupling losses. We present an integrated NEMS transducer based on a microwave cavity dielectrically coupled to an array of doubly-clamped pre-stressed silicon nitride beam resonators. This cavity-enhanced detection scheme allows resolving the resonators' Brownian motion at room temperature while preserving their high mechanical quality factor of 290,000 at 6.6 MHz. Furthermore, our approach constitutes an "opto"mechanical system in which backaction effects of the microwave field are employed to alter the effective damping of the resonators. In particular, cavity-pumped self-oscillation yields a linewidth of only 5 Hz. Thereby, an adjustement-free, all-integrated and self-driven nanoelectromechanical resonator array interfaced by just two microwave connectors is realised, potentially useful for applications in sensing and signal processing

Material Culture and Military History: Test-Firing Early Modern Small Arms

This article is in two parts. Part 1 summarizes the results of a series of test-firings of genuine early modem small arms carried out in 1988-89 by staff of the Landeszeughaus (Provincial Armoury) in Graz, Austria — a division of the Provincial Museum Administration. The results constitute the best quantitative data ever obtained about the ballistic characteristics (muzzle velocity, accuracy on target, penetrat-ing power of bullets) of early modern military small arms. Part 2 interprets the significance if the test findings. Early modern small arms under the best of circumstances were extremely inaccurate. Bullets lost most of their kinetic energy within 30-50 metres of flight. Pistols, however, tested better than might have been expected. The results confirm the views of some historians giving more weight to the role of the pistol in challenging the supremacy of the heavily armoured knight. This article demon-strates how information from material history is relevant to sweeping historical theses. Résumé Cet article est divisé en deux parties. Dans la première, Krenn et Kalaus résument les résul-tats d'une série de tirs d'essai d'armes légères authentiques des débuts de l'ère moderne, effectués en 1988-1989 par le personnel du Landeszeughaus (manège militaire provincial) de Graz, en Autriche, une division de l'Admi-nistration du musée provincial. Les résultats obtenus constituent les meilleures données quantitatives jamais recueillies au sujet des caractéristiques balistiques (vitesse initiale, justesse du tir, pouvoir de pénétration des balles) des armes légères utilisées à l'époque à des fins militaires. Dans la deuxième partie, Hall interprète les résultats de ces essais. Les armes légères des débuts de l'ère moderne étaient, même dans les meilleures circonstances, extrêmement imprécises. Les balles perdaient la majeure partie de leur énergie cinétique dans les 30 à 50 premiers mètres de vol. Les pistolets, cependant, ont donné lors des essais de meilleurs résultats que prévu. Ces résultats confirment les vues de certains historiens, qui estiment que le pistolet a joué un rôle important dans la disparition de l'armement lourd du chevalier. Cet article vise à démontrer la pertinence de l'information tirée de l'histoire matérielle pour illustrer les thèses historiques générales

Non-adiabatic dynamics of two strongly coupled nanomechanical resonator modes

The Landau-Zener transition is a fundamental concept for dynamical quantum systems and has been studied in numerous fields of physics. Here we present a classical mechanical model system exhibiting analogous behaviour using two inversely tuneable, strongly coupled modes of the same nanomechanical beam resonator. In the adiabatic limit, the anticrossing between the two modes is observed and the coupling strength extracted. Sweeping an initialized mode across the coupling region allows mapping of the progression from diabatic to adiabatic transitions as a function of the sweep rate

Magnetic dilution by severe plastic deformation

Mixtures of Fe and Cu powders are cold-compacted and subsequently deformed with severe plastic deformation by high-pressure torsion, leading to bulk samples. The dilution of Fe in the Cu matrix is investigated with SQUID-magnetometry, whereas the magnetic properties change as a function of Fe-content from a frustrated regime to a thermal activated behaviour. The magnetic properties are correlated with the microstructure, investigated by synchrotron X-ray diffraction and atom probe tomography. Annealing of the as-deformed states leads to demixing and grain growth, with the coercivity as a function of annealing temperature obeying the random anisotropy model. The presented results show that high-pressure torsion is a technique capable to affect the microstructure even on atomic length scales

Tuneable Magneto-Resistance by Severe Plastic Deformation

Bulk metallic samples were synthesized from different binary powder mixtures consisting of elemental Cu, Co, and Fe using severe plastic deformation. Small particles of the ferromagnetic phase originate in the conductive Cu phase, either by incomplete dissolution or by segregation phenomena during the deformation process. These small particles are known to give rise to granular giant magnetoresistance. Taking advantage of the simple production process, it is possible to perform a systematic study on the influence of processing parameters and material compositions on the magneto-resistance. Furthermore, it is feasible to tune the magnetoresistive behavior as a function of the specimens chemical composition. It was found that specimens of low ferromagnetic content show an almost isotropic drop in resistance in a magnetic field. With increasing ferromagnetic content, percolating ferromagnetic phases cause an anisotropy of the magnetoresistance. By changing the parameters of the high pressure torsion process, i.e., sample size, deformation temperature, and strain rate, it is possible to tailor the magnitude of giant magneto-resistance. A decrease in room temperature resistivity of approx. 3.5% was found for a bulk specimen containing an approximately equiatomic fraction of Co and Cu

Multipitched plasmonic nanoparticle grating for broadband light enhancement in white light‑emitting organic diodes

We apply regular arrays of plasmonic nanodisks to enhance light emission from an organic white light-emitting diode (WOLED). To achieve broadband enhancement, we apply, first, aluminum as a nanodisk material with moderate loss throughout the whole visible spectral range. Second, broadband light coupling is mediated by surface lattice resonances from a multipitch array built from two superimposed gratings with different grating constants formed by elliptic and circular nanodisks. To demonstrate the viability of this concept, the grating structure was embedded in the hole transport layer of a solution-processed phosphorescent WOLED exhibiting a current efficiency of 2.1 cd/A at 1000 cd/m2. The surface lattice resonances in the grating raise the current efficiency of the device by 23% to 2.6 cd/A at 1000 cd/m2, while the device emission changes from a neutral white to a warm white appearance with CIE1931 (x,y) coordinates of (0.361, 0.352) and (0.404, 0.351), respectively. The WOLED was characterized in detail optically by extinction and angle-resolved photoluminescence and as well by electroluminescence measurements for its opto-electronic characteristics. The experimental results agree well with finite-difference time domain simulations that aim at a better understanding of the underlying physical mechanisms. In summary, our work presents a novel versatile approach for achieving broadband enhancement of light emission in WOLEDs over a wide spectral range.Peer Reviewe