Unconventional domain wall magnetoresistance of patterned Ni/Nb bilayer structures below superconducting transition temperature of Nb

Scattering of spin-up and spin-down electrons while passing through a ferromagnetic domain wall leads to an additional resistance for transport current, usually observed prominently in constricted magnetic structures. In this report, we use the resistance of the domain wall as a probe to find indirect signatures of the theoretically predicted spin-singlet supercurrent to spin-triplet supercurrent conversion effect of ferromagnetic domain walls. Here we examine the domain wall induced resistance in Ni stripe in a bilayer Ni/Nb geometry in the normal state and in the superconducting state of Nb. By making a 6um wide gap in the top Nb layer we routed the transport current through the Ni layer in the normal state and in the superconducting state of Nb. In the normal state of Nb, in-field transport measurements showed a clear domain wall magneto-resistance (DWMR) peak near the coercive field, where the domain wall density is expected to be maximum. Interestingly, however, below the superconducting transition temperature of Nb, the DWMR peak of the Ni layer showed a sharp drop in the field range where the number of domain walls becomes maximum. This observation may be a possible signature of magnetic domain wall induced spin-triplet correlations in the Ni layer due to the direct injection of spin-singlet Cooper pairs from Nb into the magnetic domain walls

Are diabetes self-management interventions delivered in the psychiatric inpatient setting effective?: A protocol for a systematic review

Introduction: Diabetes is a major risk factor for cardiovascular disease, which is the most significant contributor to increased mortality due to natural causes in those with severe mental illness (SMI). Self-management interventions for diabetes have been shown to be effective in the general population, however, effects of these interventions in those with SMI is still unclear. Psychiatric admission could be used opportunistically to deliver interventions of this kind and help improve diabetes self-management. This review aims to assess whether interventions of this kind improve diabetes outcomes and have an effect on reducing cardiovascular risk. Methods and analysis: This review will include studies assessing diabetes self-management interventions designed to be delivered to those aged 18 and over with comorbid type 2 diabetes and SMI during admission to psychiatric inpatient settings. Databases including the Cochrane Library, Medline, Psychinfo, CINAHL, Embase, WHO’s International Clinical Trials Registry Platform, International Health Technology Assessment Database, UK Clinical Research Network and ClinicalTrials.gov will be searched from inception to September 2022. Where possible, meta-analysis of included studies will be conducted. If heterogeneity is high and meta-analysis is not possible, we will use other means of data synthesis and will include a narrative description of included studies. Ethics and dissemination: Ethical approval is not required as the systematic review will only include data from existing studies. The results will be disseminated via peer-reviewed publication and presentation at relevant national and international conferences. PROSPERO registration number: CRD4202235767

Community Health Centers and Medicaid Payment Reform: Emerging Lessons from Medicaid Expansion States

Community health centers represent a major source of primary health care for the nation’s Medicaid beneficiaries. Because the Federally Qualified Health Center (FQHC) payment system is encounter-based, health centers and Medicaid agencies in ACA expansion states are actively pursuing payment reforms that will enable health centers to adopt strategies that can more effectively respond to the considerable and complex health and social needs of people served by health centers, and more efficiently address the surging volume of patient care. In five expansion states whose alternative payment experiments are underway, health centers and Medicaid agencies are testing payment alternatives, such as global payments, that link payment to performance while ensuring that the FQHC hold-harmless standard is met and that total revenues do not fall below the FQHC floor. These alternative payment approaches enable health centers to test new strategies to address the needs of their patients, while enabling state agencies to align these strategies more closely with broader payment reform efforts

Superconducting exchange coupling between ferromagnets.

Recent discoveries from superconductor (S)/ferromagnet (FM) heterostructures include π-junctions, triplet pairing, critical temperature (Tc) control in FM/S/FM superconducting spin valves (SSVs) and critical current control in S/FM/N/FM/S spin valve Josephson junctions (N: normal metal). In all cases, the magnetic state of the device, generally set by the applied field, controls the superconducting response. We report here the observation of the converse effect, that is, direct superconducting control of the magnetic state in GdN/Nb/GdN SSVs. A model for an antiferromagnetic effective exchange interaction based on the coupling of the superconducting condensation energy to the magnetic state can explain the Nb thickness and temperature dependence of this effect. This superconducting exchange interaction is fundamentally different in origin from the various exchange coupling phenomena that underlie conventional spin electronics (spintronics), and provides a mechanism for the active control of the magnetic state in superconducting spintronics.This work was supported by ERC AdG ‘Superspin’ and EPSRC Programme Grant EP/N017242/1.This is the author accepted manuscript. The final version is available from Nature Publishing Group at http://dx.doi.org/10.1038/nmat475

Community Health Centers: A 2013 Profile and Prospects as ACA Implementation Proceeds

In 2013, more than 1,200 federally funded community health centers provided access to care for low-income populations living in medically underserved communities throughout the country. The Affordable Care Act made expansion of health centers a key part of its strategy for ensuring that these communities would realize the benefits of increased health insurance coverage for their residents. As health insurance coverage expands under the Affordable Care Act (ACA) and the demand for primary care increases, the role of health centers is likely to increase. A key question going forward is whether health centers’ expanded capacity, developed over the past five years, will be sustained going forward

Nano-optical observation of cascade switching in a parallel superconducting nanowire single photon detector

The device physics of parallel-wire superconducting nanowire single photon detectors is based on a cascade process. Using nano-optical techniques and a parallel wire device with spatially-separate pixels we explicitly demonstrate the single- and multi-photon triggering regimes. We develop a model for describing efficiency of a detector operating in the arm-trigger regime. We investigate the timing response of the detector when illuminating a single pixel and two pixels. We see a change in the active area of the detector between the two regimes and find the two-pixel trigger regime to have a faster timing response than the one-pixel regime.Comment: 11 pages, 2 figure

Measurement of thin film magnetostriction using field-dependent atomic force microscopy

Measurement of thin film magnetostriction is a challenging task, as magnetostrictive material deformations in parts per million, in conjunction with materials at small dimensions, require high precision, often with dedicated set-ups, for reproducible results. We have developed a novel approach employing a commercial atomic force microscope (AFM) with attached electromagnets. Magnetostriction measurements are demonstrated on 50 - 500 nm thick Fe81Al19 films sputter deposited directly on high aspect ratio commercial AFM micro-cantilevers. A magnetostrictive deflection of the cantilever bimorph translates into a deflection force acting in a contact mode measurement, which is interpreted and recorded as a change in height. For determination of the magnetostriction coefficient, we have developed a modified version of the equation for the magnetostrictive deflection of a cantilever bimorph by Guerrero and Wetherhold, taking into account long-range attractive forces acting during contact mode AFM measurements in air. The sub-atomic precision of the AFM, combined with the widespread availability of all components and the simple set-up, makes the measurement of magnetostriction on films of just a few tens of nanometers thickness easily accessible.H2020-MSCA-ITN-2014 SELECTA (grant agreement no. 642642 of the European Commission

Domain wall induced modulation of low field H-T phase diagram in patterned superconductor-ferromagnet stripes

We present a systematic study of the magnetic domain wall induced modulation of superconducting transition temperature (Tc) in Nb/Ni bilayer stripes. By varying the thickness of the Ni layer from 20 nm to 100 nm we have been able to measure the low field Tc-H phase diagram spanning the N´eel domain wall and Bloch domain wall range of thicknesses. Micromagnetic simulations and magnetic force microscopy measurements confirmed a stronger out-of-plane stray field in the Bloch domain walls compared to the N´eel walls. A suppression in Tc was observed in the magnetization reversal region of the Ni film, the magnitude of which followed linearly to the strength of the out-of-plane stray field due to the domain walls. The magnitude of the stray field was quantified by comparing the Tc of the suppressed region of H-Tc phase diagrams with the unaffected part of the H-Tc curve. With Bloch domain walls a change in Tc of more than 60 mK was observed which is much more compared to the earlier reports. We believe that the narrow stripe geometry of the bilayers and the transverse external field maximized the effect of the domain walls in the Ni layer on the overlying superconducting film, leading to a larger change in Tc. This observation may be useful for domain wall controlled switching devices in superconducting spintronics