Proximity effect in [Nb(1.5nm)/Fe(x)]10_{10}/Nb(50nm) superconducting/ferromagnet heterostructures

We have investigated the structural, magnetic and superconducting properties of [Nb(1.5nm)/Fe(x)]$_{10}$ superlattices deposited on a thick Nb(50nm) layer. Our investigation showed that the Nb(50nm) layer grows epitaxially at 800$^\circ$C on Al$_2$O$_3$(1$\bar{1}$02) substrate. Samples grown at this condition posses a high residual resistivity ratio of 15-20. By using neutron reflectometry we show that Fe/Nb superlattices with $x<$ 4 nm form a depth-modulated FeNb alloy with concentration of iron varying between 60% and 90%. This alloy has properties of a weak ferromagnet. Proximity of this weak ferromagnetic layer to a thick superconductor leads to an intermediate phase that is characterized by co-existing superconducting and normal-state domains. By increasing the thickness of the Fe layer to $x$ = 4 nm the intermediate phase disappears. We attribute the intermediate state to proximity induced non-homogeneous superconductivity in the periodic Fe/Nb structure

Resonant neutron reflectometry for hydrogen detection

The detection and quantification of hydrogen is becoming increasingly important in research on electronic materials and devices, following the identification of the hydrogen content as a potent control parameter for the electronic properties. However, establishing quantitative correlations between the hydrogen content and the physical properties of solids remains a formidable challenge. Here we report neutron reflectometry experiments on 50 nm thick niobium films during hydrogen loading, and show that the momentum-space position of a prominent waveguide resonance allows tracking of the absolute hydrogen content with an accuracy of about one atomic percent on a timescale of less than a minute. Resonance-enhanced neutron reflectometry thus allows fast, direct, and non-destructive measurements of the hydrogen concentration in thin-film structures, with sensitivity high enough for real-time in-situ studies

Hydrogen detection in thin films by resonant neutron reflectometry

A new methodology to measure in situ absorbed hydrogen concentration in thin films with in- creased sensitivity and faster measurement times with respect to conventional reflectometry methods was recently developed at the reflectometer NREX at the MLZ. The method is based on the linear relation between the incorporated hydrogen concentration and the shift in momentum transfer of a resonant mode arising due to waveguide effects

A randomized split-face clinical trial of conventional vs indoor-daylight photodynamic therapy for the treatment of multiple actinic keratosis of the face and scalp and photoaging

9noRecently, indoor daylight photodynamic therapy (idl-PDT) has been developed; however, its efficacy and tolerability remain to be assessed.restrictedrestrictedArisi, M; Rossi, M T; Spiazzi, L; Guasco Pisani, E; Venturuzzo, A; Rovati, C; Tomasi, C; Venturini, M; Calzavara-Pinton, P GArisi, M; Rossi, M T; Spiazzi, L; Guasco Pisani, E; Venturuzzo, A; Rovati, C; Tomasi, C; Venturini, M; Calzavara-Pinton, P