Survey participation as a function of democratic engagement, trust in institutions, and perceptions of surveys

Objective: With response rates of large-scale surveys having decreased significantly over the years and rebounds seeming unlikely, many studies now examine how response rates vary with methodological design and incentives. This investigation delves into how individual-level factors shape survey participation. Specifically, we examine the influence of individuals’ democratic engagement and their trust in institutions on intent to participate in surveys, both directly and indirectly through their perceptions of surveys. Methods: We collected survey data from a probability sample of adults (N = 1343) in Mannheim, Germany, from November 2019 to March 2020. Structural equation models were estimated to test the hypothesized relationships. Results: The analyses support most, but not all, hypothesized relationships. Democratic engagement bolstered intent to participate, directly as well as indirectly through perceptions of surveys. Institutional trust, on the other hand, only influenced the outcome measure indirectly. Perceptions of surveys had a strong bearing overall effect on intent to participate. Conclusion: The study's results suggest that the response rates and larger issues related to the perceived legitimacy of public opinion and survey research might be intertwined with orientations related to people's civic and political life. The article discusses potential ways survey researchers can counteract distrust in surveys

Ultrafast optically induced spin transfer in ferromagnetic alloys

The vision of using light to manipulate electronic and spin excitations in materials on their fundamental time and length scales requires new approaches in experiment and theory to observe and understand these excitations. The ultimate speed limit for all-optical manipulation requires control schemes for which the electronic or magnetic subsystems of the materials are coherently manipulated on the time scale of the laser excitation pulse. In our work, we provide experimental evidence of such a direct, ultrafast, and coherent spin transfer between two magnetic subsystems of an alloy of Fe and Ni. Our experimental findings are fully supported by time-dependent density functional theory simulations and, hence, suggest the possibility of coherently controlling spin dynamics on subfemtosecond time scales, i.e., the birth of the research area of attomagnetism

Ultrafast optically induced spin transfer in ferromagnetic alloys

The vision of using light to manipulate electronic and spin excitations in materials on their fundamental time and length scales requires new approaches in experiment and theory to observe and understand these excitations. The ultimate speed limit for all-optical manipulation requires control schemes for which the electronic or magnetic subsystems of the materials are coherently manipulated on the time scale of the laser excitation pulse. In our work, we provide experimental evidence of such a direct, ultrafast, and coherent spin transfer between two magnetic subsystems of an alloy of Fe and Ni. Our experimental findings are fully supported by time-dependent density functional theory simulations and, hence, suggest the possibility of coherently controlling spin dynamics on subfemtosecond time scales, i.e., the birth of the research area of attomagnetism

Phage capsid nanoparticles with defined ligand arrangement block influenza virus entry

Multivalent interactions at biological interfaces occur frequently in nature and mediate recognition and interactions in essential physiological processes such as cell-to-cell adhesion. Multivalency is also a key principle that allows tight binding between pathogens and host cells during the initial stages of infection. One promising approach to prevent infection is the design of synthetic or semisynthetic multivalent binders that interfere with pathogen adhesion1,2,3,4. Here, we present a multivalent binder that is based on a spatially defined arrangement of ligands for the viral spike protein haemagglutinin of the influenza A virus. Complementary experimental and theoretical approaches demonstrate that bacteriophage capsids, which carry host cell haemagglutinin ligands in an arrangement matching the geometry of binding sites of the spike protein, can bind to viruses in a defined multivalent mode. These capsids cover the entire virus envelope, thus preventing its binding to the host cell as visualized by cryo-electron tomography. As a consequence, virus infection can be inhibited in vitro, ex vivo and in vivo. Such highly functionalized capsids present an alternative to strategies that target virus entry by spike-inhibiting antibodies5 and peptides6 or that address late steps of the viral replication cycle

Laser Induced Creation of Antiferromagnetic 180 Degree Domains in NiO Pt Bilayers

The antiferromagnetic order in heterostructures of NiO Pt thin films can be modified by optical pulses. After the irradiation with laser light, the optically induced creation of antiferromagnetic domains can be observed by imaging the created domain structure utilizing the X ray magnetic linear dichroism effect. The effect of different laser polarizations on the domain formation can be studied and used to identify a polarization independent creation of 180 domain walls and domains with 180 different N el vector orientation. By varying the irradiation parameters, the switching mechanism can be determined to be thermally induced. This study demonstrates experimentally the possibility to optically create antiferromagnetic domains, an important step towards future functionalization of all optical switching mechanisms in antiferromagnet

The 2021 ultrafast spectroscopic probes of condensed matter roadmap

In the 60 years since the invention of the laser, the scientific community has developed numerous fields of research based on these bright, coherent light sources, including the areas of imaging, spectroscopy, materials processing and communications. Ultrafast spectroscopy and imaging techniques are at the forefront of research into the light–matter interaction at the shortest times accessible to experiments, ranging from a few attoseconds to nanoseconds. Light pulses provide a crucial probe of the dynamical motion of charges, spins, and atoms on picosecond, femtosecond, and down to attosecond timescales, none of which are accessible even with the fastest electronic devices. Furthermore, strong light pulses can drive materials into unusual phases, with exotic properties. In this roadmap we describe the current state-of-the-art in experimental and theoretical studies of condensed matter using ultrafast probes. In each contribution, the authors also use their extensive knowledge to highlight challenges and predict future trends

Normal-incidence x-ray standing-wave study of copper phthalocyanine submonolayers on Cu(111) and Au(111)

Understanding the adsorption and growth mechanisms of large pi-conjugated molecules on noblemetal surfaces is a crucial aspect for designing and optimizing electronic devices based on organic materials. The investigation of adsorption heights for these molecules on different surfaces can be a direct measure for the strength of the adsorbate-substrate interaction, and gives insight into the fundamental bonding mechanisms. However, the adsorption strength is often also influenced by intermolecular (lateral) interactions which cause, e. g., island formation in the submonolayer regime and influence the adsorption geometry of individual molecules. The lateral structure can then dominate the vertical structure formation and influence the adsorbate-substrate interaction. In this context, the adsorption of copper-phthalocyanines on noble metal surfaces [Au(111), Ag(111), and Cu(111)] represents an ideal model system since the lateral structure formation, as well as the molecular adsorption geometries, strongly depend on coverage and temperature, and hence can be tuned easily. We demonstrate that for CuPc/Au(111), a system dominated by physisorption, the adsorption height of the molecules is independent from the lateral adsorption geometry. In contrast, a strong chemisorption of CuPc on Cu(111) shows a clear gradient in the interaction strength: Individual molecules in diluted phases are significantly stronger bonded than molecules in dense phases. This finding quantifies the increase of the exchange correlation in the binding process, which goes along with the tendency to a more site-specific adsorption geometry at small coverages