Freiraumqualität statt Abstandsgrün. - Band 1

Deutsche Forschungsgemeinschaft

Determination of the direct band-gap energy of InAlAs matched to InP by photoluminescence excitation spectroscopy

A series of InxAl1-xAs samples (0.51≪x≪0.55)coherently grown on InP was studied in order to measure the band-gap energy of the lattice matched composition. As the substrate is opaque to the relevant photon energies, a method is developed to calculate the optical absorption coefficient from the photoluminescence excitation spectra. The effect of strain on the band-gap energy has been taken into account. For x=0.532, at 14 K we have obtained Eg0=1549±6 meV

Calculation of Franck-Condon factors including anharmonicity: simulation of the C2 H4+ X̃2B 3u←C2 H4X̃1 Ag band in the photoelectron spectrum of ethylene

Our new simple method for calculating accurate Franck-Condon factors including nondiagonal (i.e., mode-mode) anharmonic coupling is used to simulate the C2H4+X2B 3u←C2H4X̃1 Ag band in the photoelectron spectrum. An improved vibrational basis set truncation algorithm, which permits very efficient computations, is employed. Because the torsional mode is highly anharmonic it is separated from the other modes and treated exactly. All other modes are treated through the second-order perturbation theory. The perturbation-theory corrections are significant and lead to a good agreement with experiment, although the separability assumption for torsion causes the C2 D4 results to be not as good as those for C2 H4. A variational formulation to overcome this circumstance, and deal with large anharmonicities in general, is suggested

Differential sensitivity to tonal frequency and to the rate of modulation of broad-band noise by hearing-impaired listeners

This dissertation examined whether a hearing impairment of the auditory end-organ has the same or a differential effect on the place and periodicity processes. Differential sensitivities for four normally hearing listeners and for both ears of five patients with unilateral Meniere’s disease were measured for tonal frequency and rate of sinusoidally amplitude-modulated noise at common frequencies and rates of the stimulus.

Trends and gaps in the academic literature on EU labour migration policies. CEPS Paper in Liberty and Security No. 50/December 2012

This paper provides an overview of the ‘state of the art’ in the academic literature on EU labour migration policies. It forms part of the research agenda of Work Package 18 of the NEUJOBS project, which aims at reviewing legislation and practices regarding the labour market inclusion and protection of rights of different categories of foreign workers in European labour markets. Accordingly, particular attention is paid to the works of scholars who evaluate the status of rights of third-country national workers in relation to labour market access, employment security, social integration, etc., in European legislation on labour immigration. More specifically, the review has selected those scholarly works that focus specifically on analysing the manner in which policy-makers have addressed the granting of rights to non-EU migrant workers, and the manner in which policy agendas – through the relevant political and institutional dynamics – have found their translation in the legislation adopted. This paper consists of two core parts. In the first section, it reviews the works of scholars who have touched on these research questions with respect to the internal dimensions of EU labour migration policies. The second section does the same for the external dimensions of these policies. Both sections start off by analysing the main trends in the literature that reviews these questions for the internal and external dimensions of European migration policies as a whole, and then move on to how these ‘trends’ can (or cannot) be found translated in scholarly writings on labour migration policies more specifically. In the final section, the paper concludes by summarising the main trends and gaps in the literature reviewed, and indicates avenues for further research.

First CRDS-measurements of water vapour continuum in the 940nm absorption band

Measurements of near-infrared water vapour continuum using continuous wave cavity ring down spectroscopy (cw- CRDS) have been performed at around 10611.6 and 10685:2 cm1. The continuum absorption coefficients for N2- broadening have been determined for two temperatures and wavenumbers. These results represent the first near-IR continuum laboratory data determined within the complex spectral environment in the 940nm water vapour band and are in reasonable agreement with simulations using the semiempirical CKD formulation.

Sufficiency of Favard's condition for a class of band-dominated operators on the axis

The purpose of this paper is to show that, for a large class of band-dominated operators on $\ell^\infty(Z,U)$, with $U$ being a complex Banach space, the injectivity of all limit operators of $A$ already implies their invertibility and the uniform boundedness of their inverses. The latter property is known to be equivalent to the invertibility at infinity of $A$, which, on the other hand, is often equivalent to the Fredholmness of $A$. As a consequence, for operators $A$ in the Wiener algebra, we can characterize the essential spectrum of $A$ on $\ell^p(Z,U)$, regardless of $p\in[1,\infty]$, as the union of point spectra of its limit operators considered as acting on $\ell^p(Z,U)$.