398 research outputs found
0- transition in magnetic triplet superconductor Josephson junctions
We examine a Josephson junction involving two arbitrary equal-spin-pairing
unitary triplet superconductors and a ferromagnetic tunneling barrier. Using
perturbation theory, we show how the interaction of the barrier moment with the
spin of the tunneling triplet Cooper pairs can reverse the sign of the
Josephson charge current. This also results in a Josephson spin current, which
contains a phase-independent contribution due to reflection processes at the
barrier. We verify our analytic predictions using a non-perturbative
Bogoliubov-de Gennes method.Comment: 4 pages, 2 figures, RevTeX, version accepted to PR
Men at the heart of mothering: Finding mother in Finding Nemo
After years of perpetuating myths of the subservient, ever-cheerful woman (or killing a maternal figure off at the start of a movie), Disney explored new ground in its blockbuster, Finding Nemo. Building on previous Disney critique by Elizabeth Bell and others, I argue that this film provides an expanded notion of who 'mother' is and what 'mothering' means. Firstly, I provide a brief review of social 'mothering', summarizing maternal functions as discussed by various feminist scholars. Secondly, I create a typology that assists our understanding of how Disney traditionally defines mothering in its discourse. Using elements of this typology, I then explore the ways in which Marlin, the father in Nemo, is engaged in mothering. Finally, I discuss the potential impact on viewers of portraying men as mothers and what has occurred in Disney films post-Nemo with regards to images of mothering
Telecentric F-theta fisheye lens for space applications
A very wide angle lens with a field of view of 360°x180° - a fisheye lens - has been designed to be used in a space environment. As a case study, the lens is assumed to be mounted on a spinning probe passing through a comet’s tail. The lens, rotating with the probe passing through the comet coma, may map the entire sky as viewed from the interior tail, providing unprecedented data on the spatial distribution of plasma and dust. Considering the foreseen space applications for the lens, radiation hardened glass has been taken into account for the design. A key feature of the lens is the “angular scale” uniformity (F-theta) of the sky distribution map projected on the focal plane allowing to obtain a reliable whole sky reconstruction. Care has also been taken to obtain an almost telecentric design, in order to permit filters placed on the focal plane to work properly. A telecentric fisheye operating with a pixel-limited resolution in the waveband from 500 nm up to 770 nm and with an F-theta distortion is presented in this paper
Charge Order in the Falicov-Kimball Model
We examine the spinless one-dimensional Falicov-Kimball model (FKM) below
half-filling, addressing both the binary alloy and valence transition
interpretations of the model. Using a non-perturbative technique, we derive an
effective Hamiltonian for the occupation of the localized orbitals, providing a
comprehensive description of charge order in the FKM. In particular, we uncover
the contradictory ordering roles of the forward-scattering and backscattering
itinerant electrons: the latter are responsible for the crystalline phases,
while the former produces the phase separation. We find an Ising model
describes the transition between the phase separated state and the crystalline
phases; for weak-coupling we present the critical line equation, finding
excellent agreement with numerical results. We consider several extensions of
the FKM that preserve the classical nature of the localized states. We also
investigate a parallel between the FKM and the Kondo lattice model, suggesting
a close relationship based upon the similar orthogonality catastrophe physics
of the associated single-impurity models.Comment: 39 pages, 6 figure
The Year That Was
AUSTRALIA 1989, CANADA 1988, INDIA 1988, INDIA 1989, PAKISTAN 1988, PAKISTAN 1989, SRI LANKA 1989, SOUTH AFRICA 1987
Transport Properties in Ferromagnetic Josephson Junction between Triplet Superconductors
Charge and spin Josephson currents in a ballistic
superconductor-ferromagnet-superconductor junction with spin-triplet pairing
symmetry are studied using the quasiclassical Eilenberger equation. The gap
vector of superconductors has an arbitrary relative angle with respect to
magnetization of the ferromagnetic layer. We clarify the effects of the
thickness of ferromagnetic layer and magnitude of the magnetization on the
Josephson charge and spin currents. We find that 0-\pi transition can occur
except for the case that the exchange field and d-vector are in nearly
perpendicular configuration. We also show how spin current flows due to
misorientation between the exchange field and d-vector.Comment: 6 pages, 8 figure
Microscopic derivation of Ginzburg-Landau equations for coexistent states of superconductivity and magnetism
Ginzburg-Landau (GL) equations for the coexistent states of superconductivity
and magnetism are derived microscopically from the extended Hubbard model with
on-site repulsive and nearest-neighbor attractive interactions. In the derived
GL free energy a cubic term that couples the spin-singlet and spin-triplet
components of superconducting order parameters (SCOP) with magnetization
exists. This term gives rise to a spin-triplet SCOP near the interface between
a spin-singlet superconductor and a ferromagnet, consistent with previous
theoretical studies based on the Bogoliubov de Gennes method and the
quasiclassical Green's function theory. In coexistent states of singlet
superconductivity and antiferromagnetism it leads to the occurrence of
pi-triplet SCOPs.Comment: 18 page
PHP52 From Regulatory Approval to Subsidised Patient Access in the Asia-Pacific Region: A Comparison of Systems Across Australia, China, Japan, Korea, New Zealand, Taiwan And Thailand
Socializing accountability for improving primary healthcare: an action research program in rural Karnataka
The Alma Ata Declaration of 1978 invoked a socialising form of accountability through which communities and health workers participated in and were jointly accountable for primary healthcare. Aside from a few experiments, by the 1990s these ideals were quickly replaced by policy prescriptions based on increasing efficiency in data quality and reporting through the introduction of health information systems. More recently, there has been a revival of interest in community participation as a mechanism for improving the poor status of primary healthcare in developing countries through the constitution of village health committees. This paper documents and reflects on nine years of research on interventions aimed at improving primary healthcare accountability in rural Karnataka. Over this period, our focus has shifted from studying how computerised health information systems can strengthen conventional accountability systems to a period of extended participatory action research aimed at socialising accountability practices at village level. The findings from this study constitute vital knowledge for reforming the primary healthcare sector through different policy measures including the design of appropriate technology-based solutions
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