635 research outputs found
Size Dependence of the Magnetic and Electrical Properties of the Spin-Valve Transistor
The electrical and magnetic properties of the spin-valve transistor (SVT) are investigated as a function of transistor size. A new fabrication process, designed to study the size dependence of the SVT properties, uses: silicon-on-insulator (SOI) wafers, a combination of ion beam and wet etching and a negative tone photoresist (SU8) as an insulating layer. The Si/Pt emitter and Si/Au collector Schottky barrier height do not depend on the transistor dimensions. The parasitic leakage current of the Si/Au collector is, however, proportional to its area. The relative collector current change with magnetic field is 240%, independent of size, while the transfer ratio starts to decrease for SVTs with an emitter area below 25 Ă— 25 Âżm2. The maximum input current is found to be limited by the maximum current density allowed in the base (1.7 Ă— 107 A/cm2), which is in agreement with the maximum current density for spin valve
The impact of higher education on the living standards of female graduates : IFS working paper W18/25
Essays in Labour Economics
This thesis studies the interactions between parental background, education
and later life outcomes. The first chapter analyses differences across England
in the early career earnings of children from low-income families, and the role
educational differences play in explaining this variation. Children from lowincome
families who grew up in the lowest mobility areas are expected to end
up around fifteen percentiles lower in the earnings distribution at age 28 than
similar children from the highest mobility areas. Differences in educational
achievement across areas can explain 25% of this variation for men, and more
than 45% for women. This indicates that education policy can potentially play
an important role in equalising opportunities for children from low-income
families. A second chapter estimates the impact of different higher education
degrees on earnings, controlling for the impact of parental background and
prior attainment. It finds substantial variation in earnings returns within subjects
and across universities with very similar selectivity levels, suggesting degree
choices matter a lot for later-life earnings. These returns are poorly correlated
with observable degree characteristics, implying students have to make
potentially life changing degree choices based on limited information. The third
chapter estimates “mobility rates” for all English universities, subjects and degrees,
by combining access rates and labour market success of students from
low-income families. It finds that less selective institutions outperform the most
prestigious universities on this measure. Mobility rates are mostly uncorrelated
with average earnings returns, which implies that any policies which restrict
funding or access to courses with lower earnings returns can have negative implications
for mobility. The final chapter looks at the intergenerational impact
of parental unemployment. It finds a strong and persistent negative impact of
paternal unemployment on the educational achievement and home ownership
rates of women, though not of men
Profile total hip arthroplasty:a mid term follow-up study and analysis of different methods to detect lossening of uncemented total hip prostheses
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