Skipping orbits and enhanced resistivity in large-diameter InAs/GaSb antidot lattices

We investigated the magnetotransport properties of high-mobility InAs/GaSb antidot lattices. In addition to the usual commensurability features at low magnetic field we found a broad maximum of classical origin around 2.5 T. The latter can be ascribed to a class of rosetta type orbits encircling a single antidot. This is shown by both a simple transport calculation based on a classical Kubo formula and an analysis of the Poincare surface of section at different magnetic field values. At low temperatures we observe weak 1/B-periodic oscillations superimposed on the classical maximum.Comment: 4 pages, 4 Postscript figures, REVTeX, submitted to Phys Rev

Reading Across Cultures: Global Narratives, Hotels and Railway Stations

This is the final version of the article. Available from Springer Verlag via the DOI in this record.This article takes its cue from the English critic, novelist and painter John Berger. He argues that what we know determines what we see. Hotels and railway stations, though they differ in size, design and appearance, are places of temporary national and international congress that are recognized by everyone. They become visible or even iconic once their history or their role is turned into at least part of a wider narrative—in literature, film or in other arts. This provides a representative focus by which we may read a city’s or a nation’s past. In exemplifying such connections I focus first on the long-term history of Friedrichstraße station and some of the surrounding hotels in the context of the history of Berlin, situating them within the national and, by implication, also the international context. Secondly, I will consider the outbreak of the First World War in 1914 as an event in which the role of railway stations generated both personal and collective memories across cultures and over several decades

Magnetotransport in Large Diameter InAs/GaSb Antidot Lattices

We investigated the magnetotransport through high mobility InAs/GaSb antidot lattices with large antidot diameter at different temperatures and varying electron concentrations. In addition to pronounced low-field peaks already known from GaAs antidot lattices, we find an additional broad maximum at fields slightly above 2 T, which is associated with rosetta orbits surrounding one antidot. The results of a numerical analysis based on the classical Kubo formula using a hard-wall potential are in good agreement with experiment. At low temperatures we observe weak, nearly 1/B- periodic oscillations superimposed on this maximum, which may be due to quantized rosetta orbits

Surface Phonons: Theoretical Methods and Results

peer reviewedThe theoretical methods currently in use for the calculation of surface phononsurface phonon dispersion curves and how they have evolved from the phenomenological force-constant models to the present day first principles theories are discussed. A selection of paradigmatic examples for the different classes of crystal surfaces is presented with comparisons to the experimental data obtained from helium atom scattering or electron energy-loss spectroscopy. © 2020, Springer Nature Switzerland AG