Evolutionary optimization of all-dielectric magnetic nanoantennas

Magnetic light and matter interactions are generally too weak to be detected, studied and applied technologically. However, if one can increase the magnetic power density of light by several orders of magnitude, the coupling between magnetic light and matter could become of the same order of magnitude as the coupling with its electric counterpart. For that purpose, photonic nanoantennas have been proposed, and in particular dielectric nanostructures, to engineer strong local magnetic field and therefore increase the probability of magnetic interactions. Unfortunately, dielectric designs suffer from physical limitations that confine the magnetic hot spot in the core of the material itself, preventing experimental and technological implementations. Here, we demonstrate that evolutionary algorithms can overcome such limitations by designing new dielectric photonic nanoantennas, able to increase and extract the optical magnetic field from high refractive index materials. We also demonstrate that the magnetic power density in an evolutionary optimized dielectric nanostructure can be increased by a factor 5 compared to state of the art dielectric nanoantennas. In addition, we show that the fine details of the nanostructure are not critical in reaching these aforementioned features, as long as the general shape of the motif is maintained. This advocates for the feasibility of nanofabricating the optimized antennas experimentally and their subsequent application. By designing all dielectric magnetic antennas that feature local magnetic hot-spots outside of high refractive index materials, this work highlights the potential of evolutionary methods to fill the gap between electric and magnetic light-matter interactions, opening up new possibilities in many research fields.Comment: 13 pages, 4 figure

Annulment proceedings and multilevel judicial conflict

This open access book provides an exhaustive picture of the role that annulment conflicts play in the EU multilevel system. Based on a rich dataset of annulment actions since the 1960s and a number of in-depth case studies, it explores the political dimension of annulment litigation, which has become an increasingly relevant judicial tool in the struggle over policy content and decision-making competences. The book covers the motivations of actors to turn policy conflicts into annulment actions, the emergence of multilevel actors’ litigant configurations, the impact of actors’ constellations on success in court, as well as the impact of annulment actions on the multilevel policy conflicts they originate from

Reversible positioning of single molecules inside zero-mode waveguides

We have developed a hybrid nanopore/zero-mode waveguide device for single-molecule fluorescence and DNA sequencing applications. The device is a freestanding solid-state membrane with sub-5 nm nanopores that reversibly delivers individual biomolecules to the base of 70 nm diameter waveguides for interrogation. Rapid and reversible molecular loading is achieved by controlling the voltage across the device. Using this device we demonstrate protein and DNA loading with efficiency that is orders of magnitude higher than diffusion-based molecular loading.R21 HG006873 - NHGRI NIH HHS; R21-HG006873 - NHGRI NIH HHSPublished versio

Shear wave structure of a transect of the Los Angeles basin from multimode surface waves and H/V spectral ratio analysis

We use broad-band stations of the ‘Los Angeles Syncline Seismic Interferometry Experiment’ (LASSIE) to perform a joint inversion of the Horizontal to Vertical spectral ratios (H/V) and multimode dispersion curves (phase and group velocity) for both Rayleigh and Love waves at each station of a dense line of sensors. The H/V of the autocorrelated signal at a seismic station is proportional to the ratio of the imaginary parts of the Green’s function. The presence of low-frequency peaks (∼0.2 Hz) in H/V allows us to constrain the structure of the basin with high confidence to a depth of 6 km. The velocity models we obtain are broadly consistent with the SCEC CVM-H community model and agree well with known geological features. Because our approach differs substantially from previous modelling of crustal velocities in southern California, this research validates both the utility of the diffuse field H/V measurements for deep structural characterization and the predictive value of the CVM-H community velocity model in the Los Angeles region. We also analyse a lower frequency peak (∼0.03 Hz) in H/V and suggest it could be the signature of the Moho. Finally, we show that the independent comparison of the H and V components with their corresponding theoretical counterparts gives information about the degree of diffusivity of the ambient seismic field

Can monolinguals be like bilinguals? Evidence from dialect switching

Bilinguals rely on cognitive control mechanisms like selective activation and inhibition of lexical entries to prevent intrusions from the non-target language. We present cross-linguistic evidence that these mechanisms also operate in bidialectals. Thirty-two native German speakers who sometimes use the Öcher Platt dialect, and thirty-two native English speakers who sometimes use the Dundonian Scots dialect completed a dialect-switching task. Naming latencies were higher for switch than for non-switch trials, and lower for cognate compared to non-cognate nouns. Switch costs were symmetrical, regardless of whether participants actively used the dialect or not. In contrast, sixteen monodialectal English speakers, who performed the dialectswitching task after being trained on the Dundonian words, showed asymmetrical switch costs with longer latencies when switching back into Standard English. These results are reminiscent of findings for balanced vs. unbalanced bilinguals, and suggest that monolingual dialect speakers can recruit control mechanisms in similar ways as bilinguals

Determination of the resistivity anisotropy of SrRuO3_{3} by measuring the planar Hall effect

We have measured the planar Hall effect in epitaxial thin films of the itinerant ferromagnet SrRuO3 patterned with their current paths at different angles relative to the crystallographic axes. Based on the results, we have determined that SrRuO3 exhibits small resistivity anisotropy in the entire temperature range of our measurements (between 2 to 300 K); namely, both above and below its Curie temperature (~150 K). It means that in addition to anisotropy related to magnetism, the resistivity anisotropy of SrRuO3 has an intrinsic, nonmagnetic source. We have found that the two sources of anisotropy have competing effects