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Utilizing magnetic tunnel junctions (MTJs) for write/read and fast spin-orbit-torque (SOT)-driven domain-wall (DW) motion for propagation, enables non-volatile logic and majority operations, representing a breakthrough in the implementation of nanoscale DW logic devices. Recently, current-driven DW logic gates have been demonstrated via magnetic imaging, where the Dzyaloshinskii-Moriya interaction (DMI) induces chiral coupling between perpendicular magnetic anisotropy (PMA) regions via an in-plane (IP) oriented region. However, full electrical operation of nanoscale DW logic requires electrical write/read operations and a method to pattern PMA and IP regions compatible with the fabrication of PMA MTJs. Here, we study the use of a Hybrid Free Layer (HFL) concept to combine an MTJ stack with DW motion materials, and He+ ion irradiation to convert the stack from PMA to IP. First, we investigate the free layer thickness dependence of 100-nm diameter HFL-MTJ devices and find an optimal CoFeB thickness, from 7 to 10 Å, providing high tunneling magnetoresistance (TMR) readout and efficient spin-transfer torque (STT) writing. We then show that high DMI materials, like Pt/Co, can be integrated into an MTJ stack via interlayer exchange coupling with the CoFeB free layer. In this design, DMI values suitable for SOT-driven DW motion are measured by asymmetric bubble expansion. Finally, we demonstrate that He+ irradiation reliably converts the coupled free layers from PMA to IP. These findings offer a path toward the integration of fully electrically controlled DW logic circuits. [ABSTRACT FROM AUTHOR]

Background. "Life-course immunization" is increasingly recognized as important. In Italy, adults are recommended to receive influenza; pneumococcal; tetanus toxoid, reduced diphtheria toxoid, acellular pertussis (Tdap); and herpes zoster (HZ) vaccines at various ages. Study design. Cross-sectional study. Methods. To study the knowledge and attitudes of Italian general practitioners (GPs) towards adult vaccination, we surveyed 335 GPs in Piedmont from December 2019 through March 2020; and compared the results by GPs' age (=50 vs >50 years). Results. The most common vaccination information source was the regional/local educational courses (72.8%), with older vs younger GPs more likely to attend (79.4% vs 64.4%; p=0.002). Approximately half felt that they needed further information on vaccine co-administration (55.5%), duration of protection (49.6%), and safety/tolerability (48.7%), with older vs younger GPs being more interested in safety/tolerability. Overall, most respondents (86.0%) felt that information for the patient would most engage them, and 68.1% planned to co-administer vaccines. Respondents felt most comfortable proposing influenza, but were also comfortable about pneumococcal/Tdap/HZ vaccination. However, younger vs older GPs were more comfortable about proposing Tdap and HZ. The most common ways to inform patients about influenza or pneumococcal/Tdap/HZ vaccination eligibility were personally during a visit (42.7% or 54.3%, respectively) or via an information poster (30.7% or 17.9%). Conclusions. The surveyed GPs had favorable attitudes towards adult vaccination and were interested in ongoing education. [ABSTRACT FROM AUTHOR]

Sputtered [(Pt-Co).sub.n]-FeMn multilayers exhibit both perpendicular magnetic anisotropy and exchange bias at room temperature. Their magnetic properties after in-plane and perpendicular-to-plane magnetic annealing have been studied by means of extraordinary Hall effect and magnetic force microscopy or polar Kerr microscopy. A crossover from in-plane to perpendicular anisotropy was observed as a function of number of repeats n. The dynamics of magnetization switching has been investigated on both sides of the hysteresis loops. A clear asymmetry exists in the dynamics depending whether the field is parallel or antiparallel to the exchange bias field. Similarly, strong differences in the domain patterns at the coercive field were observed. Exchange-biased (Pt-Co)-Pt-(Pt-Co)-FeMn spin-valves were also investigated. Well-separated hysteresis loops were associated with the 'soft' and pinned components of the stack. These structures were used to study the interlayer coupling through the Pt spacer. Index Terms--Exchange bias, interlayer coupling, magnetic switching dynamics, perpendicular magnetic anisotropy.

Deep levels in liquid crystal phase epitaxy-grown Er-doped Si and those associated with luminescence activity are analyzed using deep level transient spectroscopy (DLTS), optical DLTS and capacitance-voltage measurements. The optical features of the material are investigated by photoluminescence, cathodoluminescence analyses. Two emission lines, A and B, are discovered, line A appeared at 0.806 eV. The results show that a real interaction happens between dislocations and Er-related emitting centers.

Studies of the effect of oxygen segregation on recombination of 60 degree dislocations and electrical properties of p-type Czochralski silicon revealed that oxygen interacts with the dislocations and oxygen segregation causes diffusion length degeneration of minority carriers. The heterogeneous and homogeneous segregation mechanisms help improve the electrical properties. The segregation reduces background short circuit current and increases the recombining activity of the dislocations.

Research into the magnetization reversal in polycrystalline exchange-coupled NiO/Co bilayers over 10 decades of field sweep rate dH/dt for varying NiO and Co thicknesses is presented. It was found that domain wall propagation and domain nucleation control the magnetization reversal and low and high sweep rates respectively.

X-ray magnetic circular dichroism (XMCD) measurements have been undertaken on the disordered Fe(sub72)Pt(sub28) Invar alloy, together with x-ray diffraction. High spin to low spin state transition was seen by both methods. XMCD provides evidence of the disappearance of the magnetic moment at high pressure and proves that an hysteresis cycle due to the pressure-dependent magnetic moment exists.

Extraordinary Hall effect and x-ray spectroscopy measurements have been performed on a series of Pt/Co/MOx trilayers (M=Al, Mg, Ta, etc.) in order to investigate the role of oxidation in the onset of perpendicular magnetic anisotropy at the Co/MOx interface. It is observed that varying the plasma oxidation time modifies the magnetic properties of the Co layer, inducing a magnetic anisotropy crossover from in plane to out of plane. We focused on the influence of plasma oxidation on Pt/Co/AlOx perpendicular magnetic anisotropy. The interfacial electronic structure is analyzed via x-ray photoelectron spectroscopy measurements. It is shown that the maximum of out-of-plane magnetic anisotropy corresponds to the appearance of a significant density of Co–O bondings at the Co/AlOx interface. [ABSTRACT FROM AUTHOR]

The effects of low-temperature annealing in 8.2 MeV electron-irradiated 4H-SiC Schottky diodes were investigated. Deep-level transient spectroscopy and minority-carrier diffusion length (Ld) measurements were carried out on not-irradiated samples and on irradiated samples before and after thermal treatments up to T=450 °C. We found that several deep levels in the upper half band gap (S1 with enthalpy ET=0.27 eV, S2 with ET=0.35 eV, S4 with ET=0.71 eV, and S5 with ET=0.96 eV) anneal out or modify at temperature values lower or equal to T=450 °C, whereby their progressive annealing out is accompanied by a net increase of Ld, up to 50% of the value in the as-irradiated sample. We drew some conclusions regarding the microscopic nature of the defects related to the deep levels, according to their annealing behavior. [ABSTRACT FROM AUTHOR]

Three electric-dipole spin-resonance signals, labeled TU7, TU8, and TU9, were detected after subjecting oxygen-rich silicon samples to two-step annealing procedures at 450 and 650 °C for prolonged times. The formation and structural evolution of large interstitial agglomerates, known as rodlike defects, occur in oxygen-rich silicon material during similar annealing procedures. Comparison of parameters and formation peculiarities of the defects, inferred from the investigation of the detected signals, with those previously reported for rodlike defects, allowed the assigning of the TU7, TU8, and TU9 spectra to the line-interstitial defects, the planar defects, and the dislocation dipoles, respectively. Correlations of the spin-resonance signals and peculiarities in the photoluminescence spectra for the samples are reported and analyzed. [ABSTRACT FROM AUTHOR]

We have performed magnetic domain imaging with spatial, temporal, and layer resolution using x-ray photoelectron emission microscopy. The element selectivity of x-ray magnetic circular dichroism allows the magnetization dynamics of the different magnetic layers in spin-valve-like FeNi/Cu/Co trilayers to be studied separately, using the time structure of synchrotron radiation. The unique possibilities of this technique have been used to study the influence of the intrinsic magnetic properties of the different layers on the magnetization dynamics and the interlayer magnetic coupling. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Photoluminescence (PL) and deep level transient spectroscopy (DLTS) measurements were used to study the origin of optical emissions in the 0.8-1.0 eV region of selected oxygen precipitated and dislocated silicon samples. It was shown that the D1 band, present in both types of samples, is the convolution of different sub-bands, narrowly spaced between 0.802 and 0.820 eV. The emission at 0.807 eV, assigned in the literature to dislocations, was found only in samples where dislocations were intentionally generated by plastic deformation or induced by the clustering of self-interstitials generated during the growth of oxide precipitates. A comparison of the results of PL, DLTS, and optical DLTS measurements allows the assignment of levels involved in the radiative recombination processes. [ABSTRACT FROM AUTHOR]

The role of interfacial oxidation in the anisotropy crossover of a thin Co layer in Pt/Co/Al[O.sub.x] sandwiches are examined. The studies have shown that increasing the oxidation time increases the amount of interfacial oxide, which is at the origin at perpendicular magnetic anisotropy.

Focuses on a study which investigated the influence of dislocations on the segregation of oxygen in Czochralski grown silicon. Selection of the study samples; Procedures for dislocation generation and thermal annealing; Factors that influence oxygen segregation.

X-ray spectroscopy measurements have been performed on a series of Pt/Co/AlOx trilayers to investigate the role of Co oxidation in the perpendicular magnetic anisotropy at the Co/AlOx interface. It is observed that varying the degree of oxidation modifies the magnetic properties of the Co layer, inducing a magnetic anisotropy crossover from in plane to out of plane. The microscopic structural properties are analyzed via x-ray photoelectron spectroscopy measurements. It is shown that increasing the oxidation time enhances the amount of interfacial oxide, which may be at the origin of perpendicular magnetic anisotropy. [ABSTRACT FROM AUTHOR]