12 research outputs found
Interference patterns of multifacet 20x(0-pi-) Josephson junctions with ferromagnetic barrier
We have realized multifacet Josephson junctions with periodically alternating
critical current density (MJJs) using
superconductor-insulator-ferromagnet-superconductor heterostructures. We show
that anomalous features of critical current vs. applied magnetic field,
observed also for other types of MJJs, are caused by a non-uniform flux density
(parallel to the barrier) resulting from screening currents in the electrodes
in the presence of a (parasitic) off-plane field component.Comment: submitted to PR
Visualizing supercurrents in ferromagnetic Josephson junctions with various arrangements of 0 and \pi segments
Josephson junctions with ferromagnetic barrier can have positive or negative
critical current depending on the thickness of the ferromagnetic layer.
Accordingly, the Josephson phase in the ground state is equal to 0 (a
conventional or 0 junction) or to ( junction). When 0 and
segments are joined to form a "0- junction", spontaneous supercurrents
around the 0- boundary can appear. Here we report on the visualization of
supercurrents in superconductor-insulator-ferromagnet-superconductor (SIFS)
junctions by low-temperature scanning electron microscopy (LTSEM). We discuss
data for rectangular 0, , 0-, 0--0 and 20 \times 0-
junctions, disk-shaped junctions where the 0- boundary forms a ring, and
an annular junction with two 0- boundaries. Within each 0 or segment
the critical current density is fairly homogeneous, as indicated both by
measurements of the magnetic field dependence of the critical current and by
LTSEM. The parts have critical current densities up to
35\units{A/cm^2} at T = 4.2\units{K}, which is a record value for SIFS
junctions with a NiCu F-layer so far. We also demonstrate that SIFS technology
is capable to produce Josephson devices with a unique topology of the 0-
boundary.Comment: 29 pages, 8 figure
Critical current diffraction pattern of SIFS Josephson junctions with step-like F-layer
We present the latest generation of
superconductor-insulator-ferromagnet-superconductor Josephson tunnel junctions
with a step-like thickness of the ferromagnetic (F) layer. The F-layer
thicknesses and in both halves were varied to obtain different
combinations of positive and negative critical current densities and
. The measured dependences of the critical current on applied magnetic
field can be well described by a model which takes into account different
critical current densities (obtained from reference junctions) and different
net magnetization of the multidomain ferromagnetic layer in both halves.Comment: 7 pages, 3 figure
Commensurability effects in superconducting Nb films with quasiperiodic pinning arrays
We study experimentally the critical depinning current Ic versus applied
magnetic field B in Nb thin films which contain 2D arrays of circular antidots
placed on the nodes of quasiperiodic (QP) fivefold Penrose lattices. Close to
the transition temperature Tc we observe matching of the vortex lattice with
the QP pinning array, confirming essential features in the Ic(B) patterns as
predicted by Misko et al. [Phys. Rev. Lett, vol.95, 177007 (2005)]. We find a
significant enhancement in Ic(B) for QP pinning arrays in comparison to Ic in
samples with randomly distributed antidots or no antidots.Comment: 4 pages, 3 figure
The LifeCycle Project-EU Child Cohort Network : a federated analysis infrastructure and harmonized data of more than 250,000 children and parents
Early life is an important window of opportunity to improve health across the full lifecycle. An accumulating body of evidence suggests that exposure to adverse stressors during early life leads to developmental adaptations, which subsequently affect disease risk in later life. Also, geographical, socio-economic, and ethnic differences are related to health inequalities from early life onwards. To address these important public health challenges, many European pregnancy and childhood cohorts have been established over the last 30 years. The enormous wealth of data of these cohorts has led to important new biological insights and important impact for health from early life onwards. The impact of these cohorts and their data could be further increased by combining data from different cohorts. Combining data will lead to the possibility of identifying smaller effect estimates, and the opportunity to better identify risk groups and risk factors leading to disease across the lifecycle across countries. Also, it enables research on better causal understanding and modelling of life course health trajectories. The EU Child Cohort Network, established by the Horizon2020-funded LifeCycle Project, brings together nineteen pregnancy and childhood cohorts, together including more than 250,000 children and their parents. A large set of variables has been harmonised and standardized across these cohorts. The harmonized data are kept within each institution and can be accessed by external researchers through a shared federated data analysis platform using the R-based platform DataSHIELD, which takes relevant national and international data regulations into account. The EU Child Cohort Network has an open character. All protocols for data harmonization and setting up the data analysis platform are available online. The EU Child Cohort Network creates great opportunities for researchers to use data from different cohorts, during and beyond the LifeCycle Project duration. It also provides a novel model for collaborative research in large research infrastructures with individual-level data. The LifeCycle Project will translate results from research using the EU Child Cohort Network into recommendations for targeted prevention strategies to improve health trajectories for current and future generations by optimizing their earliest phases of life.Peer reviewe
Imaging of order parameter induced π phase shifts in cuprate superconductors by low-temperature scanning electron microscopy
10.1103/PhysRevLett.103.067011Physical Review Letters1036-PRLT
Cohort description:measures of early-life behaviour and later psychopathology in the LifeCycle Project — EU Child Cohort Network
Abstract
Background: The EU LifeCycle Project was launched in 2017 to combine, harmonise, and analyse data from more than 250,000 participants across Europe and Australia, involving cohorts participating in the EU-funded LifeCycle Project. The purpose of this cohort description is to provide a detailed overview over the major measures within mental health domains that are available in 17 European and Australian cohorts participating in the LifeCycle Project.
Methods: Data on cognitive, behavioural and psychological development has been collected on participants from birth until adulthood through questionnaire and medical data. We developed an inventory of the available data by mapping individual instruments, domain types, and age groups, providing the basis for statistical harmonization across mental health measures.
Results: The mental health data in LifeCycle contain longitudinal and cross-sectional data for ages 0–18+ years, covering domains across a wide range of behavioural and psychopathology indicators and outcomes (including executive function, depression, ADHD and cognition). These data span a unique combination of qualitative data collected through behavioural/cognitive/mental health questionnaires and examination, as well as data from biological samples and indices in the form of brain imaging (MRI, foetal ultrasound) and DNA methylation data. Harmonized variables on a subset of mental health domains have been developed, providing statistical equivalence of measures required for longitudinal meta-analyses across instruments and cohorts.
Conclusions: Mental health data harmonized through the LifeCycle project can be used to study life course trajectories and exposure-outcome models that examine early life risk factors for mental illness and develop predictive markers for later-life disease