Uniaxial magnetocrystalline anisotropy in CaRuO3{\rm CaRuO_3}

${\rm CaRuO_3}$ is a paramagnetic metal and since its low temperature resistivity is described by $\rho=\rho_0+AT^\gamma$ with $\gamma \sim 1.5$, it is also considered a non-Fermi liquid (NFL) metal. We have performed extensive magnetoresistance and Hall effect measurements of untwinned epitaxial films of ${\rm CaRuO_3}$. These measurements reveal that ${\rm CaRuO_3}$ exhibits uniaxial magnetocrystalline anisotropy. In addition, the low-temperature NFL behavior is most effectively suppressed when a magnetic field is applied along the easy axis, suggesting that critical spin fluctuations, possibly due to proximity of a quantum critical phase transition, are related to the NFL behavior.Comment: 7 figure

Evidence of Majorana fermions in an Al - InAs nanowire topological superconductor

Majorana fermions are the only fermionic particles that are expected to be their own antiparticles. While elementary particles of the Majorana type were not identified yet, quasi-particles with Majorana like properties, born from interacting electrons in the solid, were predicted to exist. Here, we present thorough experimental studies, backed by numerical simulations, of a system composed of an aluminum superconductor in proximity to an indium arsenide nanowire, with the latter possessing strong spin-orbit coupling. An induced 1d topological superconductor - supporting Majorana fermions at both ends - is expected to form. We concentrate on the characteristics of a distinct zero bias conductance peak (ZBP), and its splitting in energy, both appearing only with a small magnetic field applied along the wire. The ZBP was found to be robustly tied to the Fermi energy over a wide range of system parameters. While not providing a definite proof of a Majorana state, the presented data and the simulations support strongly its existence

The perceived vulnerability to disease scale: Cross‐cultural measurement invariance and associations with fear of COVID‐19 across 16 countries

Using cross‐sectional data from N = 4274 young adults across 16 countries during the COVID‐19 pandemic, we examined the cross‐cultural measurement invariance of the perceived vulnerability to disease (PVD) scale and tested the hypothesis that the association between PVD and fear of COVID‐19 is stronger under high disease threat [that is, absence of COVID‐19 vaccination, living in a country with lower Human Development Index (HDI) or higher COVID‐19 mortality]. Results supported a bi‐factor Exploratory Structural Equation Modeling model where items loaded on a global PVD factor, and on the sub‐factors of Perceived Infectability and Germ Aversion. However, cross‐national invariance could only be obtained on the configural level with a reduced version of the PVD scale (PVD‐r), suggesting that the concept of PVD may vary across nations. Moreover, higher PVD‐r was consistently associated with greater fear of COVID‐19 across all levels of disease threat, but this association was especially pronounced among individuals with a COVID‐19 vaccine, and in contexts where COVID‐19 mortality was high. The present research brought clarity into the dimensionality of the PVD measure, discussed its suitability and limitations for cross‐cultural research, and highlighted the pandemic‐related conditions under which higher PVD is most likely to go along with psychologically maladaptive outcomes, such as fear of COVID‐19