Copyright and innovation: Fit for digitization?

It is contentious to what extent the existing copyright system contributes to the positive development of the regulated sectors of society. The present report shows that substantially more musical works and movies have been released in recent years than before the diffusion of digital copying technology. At the same time, the average quality of these works has been stable according to user assessments. Countries with stronger copyright protection do not exhibit greater supply of new works. Accordingly, the relatively strict copyright protection in some countries does not seem to promote the supply of new creative works. The present report also considers whether user-generated content (UGC) complements or substitutes professional content. An increasing supply of valuable UGC is not reflected in official economic statistics. In all probability, copyright protection promotes user-generated content less than professional content. As a result, substituting professional content with "amateur material" could reduce the socially desirable strength of copyright protection. However, we find that almost half of all works available on YouTube are professional content. Professional works are watched and recommended more frequently than the average. In addition, a large proportion of UGC on YouTube draws on professional works. There is little evidence that professional content would be widely replaced. It follows that UGC could also be supported by an efficient copyright system, which strengthens the supply of professional content without excessively limiting its further use as input for UGC

Measuring many-body effects in carbon nanotubes with a scanning tunneling microscope

Electron-electron interactions and excitons in carbon nanotubes are locally measured by combining Scanning tunneling spectroscopy and optical absorption in bundles of nanotubes. The largest gap deduced from measurements at the top of the bundle is found to be related to the intrinsic quasi-particle gap. From the difference with optical transitions, we deduced exciton binding energies of 0.4 eV for the gap and 0.7 eV for the second Van Hove singularity. This provides the first experimental evidence of substrate-induced gap renormalization on SWNTs

Gutachten zum Investitionsverhalten der Strom- und Gasnetzbetreiber im Rahmen des Evaluierungsberichts nach § 33 Abs. 1 ARegV. Endbericht: Projekt im Auftrag der Bundesnetzagentur

[Einleitung] Seit Anfang 2009 unterliegt die leitungsgebundene Energieversorgung in Deutschland der Anreizregulierung, durch die ein effizienter Betrieb von Strom- und Gasnetzen sichergestellt werden soll. Unklar ist allerdings, inwieweit die Anreizregulierung auch die richtigen Rahmenbedingungen für Investitionen in Ersatz und Ausbau der Netze setzt. Vor diesem Hintergrund wird in dem vorliegenden Bericht das Investitionsverhalten der Netzbetreiber untersucht. Zentrale Fragestellungen dieser Untersuchung sind: - Lassen sich relevante Einflussfaktoren auf das Investitionsverhalten der Netzbetreiber identifizieren? - Welche Rolle spielt dabei die Unterscheidung nach Art des Netzbetreibers (Verteilnetzbetreiber versus Übertragungs- und Fernleitungsnetzbetreiber, beziehungsweise Strom versus Gas)? - Hat die Einführung der Anreizregulierung ab 2009 einen nachweisbaren Einfluss auf das Investitionsverhalten? Davon unabhängig ist die Frage, ob die Netzbetreiber vor und nach Einführung der Anreizregulierung in ausreichendem Umfang investieren. Dies ist nicht Gegenstand der vorliegenden Untersuchung. Die Untersuchung basiert auf Daten und Informationen zum Investitionsverhalten der Unternehmen, die für eine repräsentative Stichprobe der Netzbetreiber in Deutschland erhoben wurden

Symmetry-selected spin-split hybrid states in C60_{60}/ferromagnetic interfaces

The understanding of orbital hybridization and spin-polarization at the organic-ferromagnetic interface is essential in the search for efficient hybrid spintronic devices. Here, using first-principles calculations, we report a systematic study of spin-split hybrid states of C$_{60}$ deposited on various ferromagnetic surfaces: bcc-Cr(001), bcc-Fe(001), bcc-Co(001), fcc-Co(001) and hcp-Co(0001). We show that the adsorption geometry of the molecule with respect to the surface crystallographic orientation of the magnetic substrate as well as the strength of the interaction play an intricate role in the spin-polarization of the hybrid orbitals. We find that a large spin-polarization in vacuum above the buckyball can only be achieved if the molecule is adsorbed upon a bcc-(001) surface by its pentagonal ring. Therefore bcc-Cr(001), bcc-Fe(001) and bcc-Co(001) are the optimal candidates. Spin-polarized scanning tunneling spectroscopy measurements on single C$_{60}$ adsorbed on Cr(001) and Co/Pt(111) also confirm that both the symmetry of the substrate and of the molecular conformation have a strong influence on the induced spin polarization. Our finding may give valuable insights for further engineering of spin filtering devices through single molecular orbitals.Comment: 10 pages, 9 figure

Localized state and charge transfer in nitrogen-doped graphene

Nitrogen-doped epitaxial graphene grown on SiC(000?1) was prepared by exposing the surface to an atomic nitrogen flux. Using Scanning Tunneling Microscopy (STM) and Spectroscopy (STS), supported by Density Functional Theory (DFT) calculations, the simple substitution of carbon by nitrogen atoms has been identified as the most common doping configuration. High-resolution images reveal a reduction of local charge density on top of the nitrogen atoms, indicating a charge transfer to the neighboring carbon atoms. For the first time, local STS spectra clearly evidenced the energy levels associated with the chemical doping by nitrogen, localized in the conduction band. Various other nitrogen-related defects have been observed. The bias dependence of their topographic signatures demonstrates the presence of structural configurations more complex than substitution as well as hole-doping.Comment: 5 pages, accepted in PR

Wachstumsfaktor Telekommunikation: Zum Beitrag der Telekommunikationsbranche zur wirtschaftlichen Entwicklung in Deutschland. Endbericht

[Einleitung] Telekommunikation ist eine Basistechnologie für wirtschaftliche Aktivitäten. Ein dynamischer, effizienter und innovativer Telekommunikationssektor leistet somit wesentliche Beiträge zum Wachstum einer Volkswirtschaft. In Deutschland war das Telekommunikationsangebot mit Ausnahme des Mobilfunks vor 1998 noch weitgehend monopolisiert. Seit der Marktöffnung des Festnetzbereichs zum Ende der 1990er Jahre und der darauf folgenden Intensivierung des Wettbewerbs hat sich die Branche sehr dynamisch entwickelt und signifikant zum Wirtschaftswachstum in Deutschland beigetragen. Dies gilt sowohl für Festnetz- und Mobilfunktelefonie, Mehrwertdienste als auch für Datenübertragung. Vor allem aufgrund des zunehmenden Datenverkehrs sowie der wachsenden Nachfrage nach höheren Übertragungsraten ist davon auszugehen, dass die Telekommunikation auch in Zukunft von hoher Bedeutung für die wirtschaftliche Entwicklung der Deutschen Volkswirtschaft sein wird. Im Rahmen dieser Studie soll die gesamtwirtschaftliche Bedeutung der Telekommunikationsbranche quantifiziert sowie die Rolle des Wettbewerbs hervorgehoben werden. Zudem soll ein Ausblick auf die Bedeutung des Wettbewerbs für die zukünftige Entwicklung der Branche gegeben werden. Der Aufbau der Studie ist wie folgt: Nach einer einleitenden Beschreibung des deutschen Telekommunikationsmarkts in Abschnitt 2, wird in Abschnitt 3.1 die Bedeutung der Telekommunikationsbranche für die deutsche Volkswirtschaft diskutiert. Soweit möglich werden die einzelnen Effekte quantifiziert. Neben den von der Branche insgesamt ausgelösten Effekten erfolgt eine Differenzierung nach Deutscher Telekom AG und Wettbewerbsunternehmen. Auf dieser Basis können Aussagen über die Bedeutung des Wettbewerbs beziehungsweise der Wettbewerbsunternehmen getroffen werden. In Abschnitt 4 folgt ein Ausblick auf die Bedeutung des Wettbewerbs in den kommenden Jahren. Abschnitt 5 beinhaltet die Schlussfolgerungen

Synthesis of Functionalized Few-Layer Graphene Through Fast Electrochemical Expansion of Graphite

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Elastic displacements and step interactions on metallic surfaces: GIXD and ab initio study of Au(332)

International audienceWe have studied the energetics, relaxation and interactions of steps on the Au(332) vicinal surface, using a combination of grazing incidence X-ray diffraction (GIXD), anisotropic linear elasticity (ALE) theory, and ab initio density functional theory (DFT). We find that the initial force distribution on a bulk-truncated surface, as well as the resulting pattern of atomic relaxations, can be reproduced excellently by a buried dipole elastic model. The close agreement obtained between experimental and calculated X-ray diffraction profiles allows us to precisely determine the value of the elastic dipole density at the steps. We also use these results to obtain an experimental estimate of the surface stress on an unreconstructed Au(111) facet, 2.3+/-0.4 Nm-1, and the value of the step-step elastic interaction energy: 950 +/- 150 meV.Å

Giant tunnel-electron injection in nitrogen-doped graphene

International audienceScanning tunneling microscopy experiments have been performed to measure the local electron injection in nitrogen-doped graphene on SiC(000¯1) and were successfully compared to ab initio calculations. In graphene, a gaplike feature is measured around the Fermi level due to a phonon-mediated tunneling channel. At nitrogen sites, this feature vanishes due to an increase of the elastic channel that is allowed because of symmetry breaking induced by the nitrogen atoms. A large conductance enhancement by a factor of up to 500 was measured at the Fermi level by comparing local spectroscopy at nitrogen sites and at carbon sites. Nitrogen doping can therefore be proposed as a way to improve tunnel-electron injection in graphene

Change of cobalt magnetic anisotropy and spin polarization with alkanethiolates self-assembled monolayers

International audience; We demonstrate that the deposition of a self-assembled monolayer of alkanethiolates on a 1 nm thick cobalt ultrathin film grown on Au(111) induces a spin reorientation transition from in-plane to out-of-plane magnetization. Using ab initio calculations, we show that a methanethiolate layer changes slightly both the magnetocrystalline and shape anisotropy, both effects almost cancelling each other out for a 1 nm Co film. Finally, the change in hysteresis cycles upon alkanethiolate adsorption could be assigned to a molecular-induced roughening of the Co layer, as shown by STM. In addition, we calculate how a methanethiolate layer modifies the spin density of states of the Co layer and we show that the spin polarization at the Fermi level through the organic layer is reversed as compared to the uncovered Co. These results give new theoretical and experimental insights for the use of thiol-based self-assembled monolayers in spintronic devices