While vortex pinning in superconductors usually becomes weaker at higher temperatures, we find the opposite behavior for a single vortex line in superfluid 4 He. The pinning steadily increases over our entire measurement range, from 0.15Tc to over 0.5Tc. We propose Kelvin waves along the vortex as a depinning mechanism with the observed temperature behavior. Pinning sites can trap vortices in a...

A plasmonic interference pattern can be formed when multiple surface plasmon waves overlap coherently. Utilizing a sharp edge coupling mechanism, we experimentally demonstrate plasmonic interference patterns that can be designed at will by shaping the edges in a metallic film. The patterns can also be dynamically tailored by adjusting the wavelength, the polarization, and the incident angle of ...

Fabrication of ultrasharp probes is of interest for many applications, including scanning probe microscopy and electron-stimulated patterning of surfaces. These techniques require reproducible ultrasharp metallic tips, yet the efficient and reproducible fabrication of these consumable items has remained an elusive goal. Here we describe a novel biased-probe field-directed sputter sharpening tec...

The simple cubic phase of a RbC60 thin film has been studied using photoelectron spectroscopy. The simple cubic-to-dimer transition is found to be reversible at the film surface. A sharp Fermi edge is observed and a lower limit of 0.5 eV is found for the surface Hubbard U, pointing to a strongly correlated metallic character of thin-film simple cubic RbC60. A molecular charge state is identifie...

The surface modes of a composite consisting of aligned metallic wires with square cross sections are investigated, on the basis of photonic band structure calculations. The effective long-wavelength dielectric response function is computed, as a function of the filling fraction. The dependence of the optical absorption on the shape of the wires and the polarization of light is discussed, and th...

UNLABELLED Accidental or intentional ingestion of sharp metallic foreign bodies is a common clinical occurrence. Predisposing factors include excessive alcohol intake, mental impairment and psychiatric illnesses. Usually, the detection of a migratory foreign body is incidental when patients present with unrelated symptoms. A 50-year-old woman attended the surgical outpatient clinic with a forei...

Helophorus dracomontanussp. n. is described from the Tibetan Plateau near Kangding, Sichuan, China. It is a member of the subgenus Helophorus s. str. but the anterolateral part of the pronotum resembles subgenus Gephelophorus Sharp, 1915. The short metallic-black maxillary palpi with almost symmetrical apical segments are suggestive of subgenus Kyphohelophorus Kuwert, 1886, but the elytral flan...

We demonstrate the design, fabrication and characterization of a near-field plasmonic nanofocusing probe with a hybrid tip-plus-aperture design. By combining template stripping with focused ion beam lithography, a variety of aperture-based near-field probes can be fabricated with high optical performance. In particular, the combination of large transmission through a C-shaped aperture aligned t...

Typically limited by the diffraction of light, most optical spectroscopy methods cannot provide the spatial resolution necessary to characterize specimens at the nanoscale. An emerging exception to this rule is tip-enhanced Raman spectroscopy (TERS), which overcomes the diffraction limit through electromagnetic field localization at the end of a sharp metallic tip. As demonstrated by the Zenobi...