Large Negative Electronic Compressibility of LaAlO3-SrTiO3 Interfaces with Ultrathin LaAlO3 Layers

A two-dimensional electron liquid is formed at the n-type interface between SrTiO3 and LaAlO3. Here we report on Kelvin probe microscopy measurements of the electronic compressibility of this electron system. The electronic compressibility is found to be negative for carrier densities of \approx10^13/cm^2. At even smaller densities, a metal-to-insulator transition occurs. These local measurements corroborate earlier measurements of the electronic compressibility of LaAlO3-SrTiO3 interfaces obtained by measuring the capacitance of macroscopic metal-LaAlO3-SrTiO3 capacitors

A Theoretical Framework of Haptic Processing in Automotive User Interfaces and Its Implications on Design and Engineering

Driving a car is a highly visual task. Despite the trend towards increased driver assistance and autonomous vehicles, drivers still need to interact with the car for both driving and non-driving relevant tasks, at times simultaneously. The often-resulting high cognitive load is a safety issue, which can be addressed by providing the driver with alternative feedback modalities, such as haptics. Recent trends in the automotive industry are moving towards the seamless integration of control elements through touch-sensitive surfaces. Psychological knowledge on optimally utilizing haptic technologies remains limited. The literature on automotive haptic feedback consists mainly of singular findings without putting them into a broader user context with respect to haptic design of interfaces. Moreover, haptic feedback has primarily been limited to the confirmation of control actions rather than the searching or finding of control elements, the latter of which becomes particularly important considering the current trends. This paper presents an integrated framework on haptic processing in automotive user interfaces and provides guidelines for haptic design of user interfaces in car interiors

Vorgehensmodell für die Auswahl elektronischer Zahlungsverfahren für E-Government

Um den Wirtschaftlichkeitsanforderungen an E-Government-Dienstleistungen gerecht zu werden, werden geeignete Zahlungsverfahren benötigt, die die effiziente und sichere Vereinnahmung von Erlösen und Gebühren ermöglichen. Anbieter von Online-Transaktionen sehen sich dabei einer unüberschaubaren Vielfalt verschiedener Zahlungsverfahren gegenüber, die von der klassischen Überweisung bis zu Mobiltelefon-basierten Zahlungsverfahren reicht. Auf Grundlage eines Anforderungskatalogs zur Auswahl elektronischer Zahlungsverfahren wird im Rahmen dieses Beitrags ein Vorgehensmodell für die Auswahl elektronischer Zahlungsverfahren für E Government-Dienstleistungen entwickelt, das die Beziehungen zwischen den einzelnen Anforderungen, die Notwendigkeit der Abwägung zwischen den Anforderungen sowie die Möglichkeit zur Kombination von Zahlungsverfahren berücksichtigt. Not only in e-business but also in e-government, the success of online services liable for costs often depends on the convenience of the payment process. To find out the most suitable payment methods for a special e-government application, the authors developed a methodical approach for e-government decision makers. The multi-dimensional decision model takes into account various requirements concerning security, economic efficiency, and specific requirements for the e-government application in question. The following paper illustrates the decision model with the case of the statistics shop of the German public authority. Based on a short classification overview of the presently existing payment methods, a sample of these payment methods is analysed and evaluated according to different substantial criteria. Then, the most suitable payment methods for the online statistics shop are selected according to the decision model.Bargeldloser Zahlungsverkehr ; Elektronischer Zahlungsverkehr ; Electronic Government ; Vorgehensmodell ; Kreditkarte; Zahlungsverfahren ; öffentliche Verwaltung; E-Payment ; E-Government

Goverment-to-Business in Deutschland

Beim Angebot elektronischer Verwaltungsdienstleistungen hinkt Deutschland weit hinterher. Bei internationalen Vergleichen belegt Deutschland nur Plätze im Mittelfeld. Insbesondere auf Ebene der Länder und der Kommunen besteht noch Nachholbedarf. Mangelnde Kundenorientierung in der Umsetzung beeinträchtigt die Akzeptanz der Angebote. Unabgestimmte Einzelprojekte verhindern die Ausschöpfung von Synergiepotenzialen. Die Rahmenbedingungen für weitere Angebote haben sich jedoch bereits deutlich verbessert. Mit DeutschlandOnline existiert eine ebenenübergreifende E-Government-Strategie. Im Bündnis für elektronische Signaturen wird die Schaffung der erforderlichen Sicherheits-Infrastruktur vorbereitet. Basiskomponenten und einzelne Best-Practice-Lösungen können bei zukünftigen Angeboten wieder verwendet werden. Erfolgreiches E-Government erfordert eine Neuausrichtung der öffentlichen Verwaltung. Die verwaltungsinternen Prozesse müssen grundlegend überarbeitet werden. Optimale Lösungen setzen eine Bündelung der Ressourcen voraus. Durch Zusammenarbeit mit privaten Anbietern können Win-Win-Situationen generiert werden. Die globale Wirtschaft erfordert länderübergreifende E-Government-Services

Two-dimensional electron liquid state at LaAlO3-SrTiO3 interfaces

Using tunneling spectroscopy we have measured the spectral density of states of the mobile, two-dimensional electron system generated at the LaAlO3-SrTiO3 interface. As shown by the density of states the interface electron system differs qualitatively, first, from the electron systems of the materials defining the interface and, second, from the two-dimensional electron gases formed at interfaces between conventional semiconductors

Diodes with Breakdown Voltages Enhanced by the Metal-Insulator Transition of LaAlO3_3-SrTiO3_3 Interfaces

Using the metal-insulator transition that takes place as a function of carrier density at the LaAlO$_3$-SrTiO$_3$ interface, oxide diodes have been fabricated with room-temperature breakdown voltages of up to 200 V. With applied voltage, the capacitance of the diodes changes by a factor of 150. The diodes are robust and operate at temperatures up to 270 C

Approximations in Fusion and Breakup reactions induced by Radioactive Beams

Some commonly used approximations for complete fusion and breakup transmission coefficients in collisions of weakly bound projectiles at near barrier energies are assessed. We show that they strongly depend on the adopted classical trajectory and can be significantly improved with proper treatment of the incident and emergent currents in the WKB approximation.Comment: 15 pages, 7 figure

Quantum longitudinal and Hall transport at the LaAlO3/SrTiO3 interface at low electron densities

We examined the magneto-transport behavior of electrons confined at the conducting LaAlO3/SrTiO3 interface in the low sheet carrier density regime. We observed well resolved Shubnikov-de Haas quantum oscillations in the longitudinal resistance, and a plateau-like structure in the Hall conductivity. The Landau indices of the plateaus in the Hall conductivity data show spacing close to 4, in units of the quantum of conductance. These experimental features can be explained by a magnetic breakdown transition, which quantitatively explains the area, structure, and degeneracy of the measured Fermi surface.Comment: 16 pages, 4 figures and 1 tabl