Adsorption, Segregation and Magnetization of a Single Mn Adatom on the GaAs (110) Surface

Density functional calculations with a large unit cell have been conducted to investigate adsorption, segregation and magnetization of Mn monomer on GaAs(110). The Mn adatom is rather mobile along the trench on GaAs(110), with an energy barrier of 0.56 eV. The energy barrier for segregation across the trenches is nevertheless very high, 1.67 eV. The plots of density of states display a wide gap in the majority spin channel, but show plenty of metal-induced gap states in the minority spin channel. The Mn atoms might be invisibl in scanning tunneling microscope (STM) images taken with small biases, due to the directional p-d hybridization. For example, one will more likely see two bright spots on Mn/GaAs(110), despite the fact that there is only one Mn adatom in the system

Family Structure and Female Labour Supply in Mexico City

This paper investigates labour supply of the wives of the heads of households in Mexico City, with a focus on the impact of family structure. A static neoclassical structural model is used. We assume that each woman chooses her labour supply and corresponding income so that her utility is maximized, conditional upon her husband’s labour supply and earnings. We use a direct translog specification, and include family composition variables as taste shifters. Also taken into account are fixed costs of working, nonlinear taxes, unobserved preference variation, prediction errors in wages of nonworkers, and potential endogeneity of wages. The models are estimated by smooth simulated maximum likelihood using data from Mexico’s Urban Employment Survey drawn in 1992. We find income elasticities of labour supply of about -0.35, and wage elasticities of about 0.5. The latter is substantially overestimated if wage rate endogeneity is not taken into account. The results are robust with respect to other specification choices. We find that the impact of family structure variables on participation is different from that on hours worked, so that their total effect is ambiguous.Female labour supply;family structure;discrete regression

A balanced way for China's inter-regional cross-border insolvency cooperation

In pursuit of solutions to China’s inter-regional cross-border insolvency cooperation, the doctoral dissertation provides 10 original recommendations accompanied with comments, which are entitled “CICIA”

Empirical studies on the labor market and on consumer demand

The thesis covers three topics on the labour market and on consumer demand. Chapters two and three focus on the labour market mobility and wage differentials between the formal sector and the informal sector in urban Mexico. Dynamic random effects panel data models are used in the analysis. Chapters four and five deal with female labour supply in Mexico and the Netherlands using a discretised structural labour supply model. While chapter four is devoted more to the empirical analysis, chapter five is more methodologically oriented and explores the nonparametric aspects of the model. Chapter six investigates household consumption and sexual bias between boys and girls in rural China by analysing Engel Curves for several commodities. In chapter six, a semiparametric approach is adopted.

Superconductivity and Phase Diagram in (Li0.8_{0.8}Fe0.2_{0.2})OHFeSe1−x_{1-x}Sx_x

A series of (Li$_{0.8}$Fe$_{0.2}$)OHFeSe$_{1-x}$S$_x$ (0 $\leq$ x $\leq$ 1) samples were successfully synthesized via hydrothermal reaction method and the phase diagram is established. Magnetic susceptibility suggests that an antiferromagnetism arising from (Li$_{0.8}$Fe$_{0.2}$)OH layers coexists with superconductivity, and the antiferromagnetic transition temperature nearly remains constant for various S doping levels. In addition, the lattice parameters of the both a and c axes decrease and the superconducting transition temperature T$_c$ is gradually suppressed with the substitution of S for Se, and eventually superconductivity vanishes at $x$ = 0.90. The decrease of T$_c$ could be attributed to the effect of chemical pressure induced by the smaller ionic size of S relative to that of Se, being consistent with the effect of hydrostatic pressure on (Li$_{0.8}$Fe$_{0.2}$)OHFeSe. But the detailed investigation on the relationships between $T_{\rm c}$ and the crystallographic facts suggests a very different dependence of $T_{\rm c}$ on anion height from the Fe2 layer or $Ch$-Fe2-$Ch$ angle from those in FeAs-based superconductors.Comment: 6 pages, 6 figure