35% magnetocurrent with spin transport through Si

Efficient injection of spin-polarized electrons into the conduction band of silicon is limited by the formation of a silicide at the ferromagnetic metal (FM)/silicon interface. In the present work, this "magnetically-dead" silicide (where strong spin-scattering significantly reduces injected spin polarization) is eliminated by moving the FM in the spin injector from the tunnel junction base anode to the emitter cathode and away from the silicon surface. This results in over an order-of-magnitude increase in spin injection efficiency, from a previously-reported magnetocurrent ratio of ~2% to ~35% and an estimated spin polarization in Si from ~1% to at least ~15%. The injector tunnel-junction bias dependence of this spin transport signal is also measured, demonstrating the importance of low bias voltage to preserve high injected spin polarization

Relative Earnings of Husbands and Wives in Urban China

This paper studies the relative contribution of husbands and wives to the family income in the process of economic transition by using the Chinese Urban Household Survey data from 1988 to 1999. We find that, contrary to the experience of western countries, the share of wives¡¦ labor earnings in urban China tends to decline slightly over time and the share of husbands¡¦ labor earnings is stable. This implies that the role of urban Chinese husbands as the main financial supporters of their families becomes relatively more important during economic transition. We argue that this trend may have reflected the restoration of the functions of household production and labor market in the process of economic transition. This restoration allows households to allocate time, effort and human capital investment for each household member and for each household and market activity in a more efficient way. Our further empirical analysis suggests that at least two factors have accounted for the strengthening of the relative importance of husbands in contributing to family income in urban China: 1) the enlargement of the positive effect of children on husbands and the opposite effect for wives; and 2) the shrinkage of the positive income effect on the leisure of husbands.