Quantum sensing

"Quantum sensing" describes the use of a quantum system, quantum properties or quantum phenomena to perform a measurement of a physical quantity. Historical examples of quantum sensors include magnetometers based on superconducting quantum interference devices and atomic vapors, or atomic clocks. More recently, quantum sensing has become a distinct and rapidly growing branch of research within the area of quantum science and technology, with the most common platforms being spin qubits, trapped ions and flux qubits. The field is expected to provide new opportunities - especially with regard to high sensitivity and precision - in applied physics and other areas of science. In this review, we provide an introduction to the basic principles, methods and concepts of quantum sensing from the viewpoint of the interested experimentalist.Comment: 45 pages, 13 figures. Submitted to Rev. Mod. Phy

How do employment effects of job creation schemes differ with respect to the foregoing unemployment duration?

Based on new administrative data for Germany covering entrances into job creation schemes between July 2000 and May 2001, we evaluate the effects of this active labour market policy programme on the employability of the participating individuals. The programme effects are estimated considering the timing of treatment in the individual unemployment spell. Applying propensity score matching in a dynamic setting where the time until treatment in the unemployment spell is stratified into quarters, regional (East and West Germany) as well as gender differences are considered in the estimation. As matching is concerned with selection on observables only, we test the robustness of the estimates against possible unobserved influences. The results in terms of employment present a mixed picture. For West Germany, most of the estimates are insignificant at the end of the observation period, but positive exceptions are found for persons starting in the fifth or ninth quarter of the unemployment spell. For East Germany, none of the groups experiences an improvement of the labour market situation. Instead, the majority of the estimates establish negative employment effects until the end of the observation period (30 months after start of programmes). Hence, job creation schemes decrease the employment chances of the participating individuals. --Evaluation,Active Labour Market Policy,Job Creation Schemes,Administrative Data,Propensity Score Matching,Hidden Bias

Identifying effect heterogeneity to improve the effiency of job creation schemes in Germany?

Previous empirical studies of job creation schemes in Germany have shown that the average effects for the participating individuals are negative. However, we find that this is not true for all strata of the population. Identifying individual characteristics that are responsible for the effect heterogeneity and using this information for a better allocation of individuals therefore bears some scope for improving programme efficiency. We present several stratification strategies and discuss the occurring effect heterogeneity. Our findings show that job creation schemes do neither harm nor improve the labour market chances for most of the groups. Exceptions are long-term unemployed men in West and long-term unemployed women in East and West Germany who benefit from participation in terms of higher employment rates. JEL: C13 , J68 , H4

The effects of vocational training programmes on the duration of unemployment in Eastern Germany

Vocational training programmes have been the most important active labour market policy instrument in Germany in the last years. However, the still unsatisfying situation of the labour market has raised doubt on the efficiency of these programmes. In this paper, we analyse the effects of the participation in vocational training programmes on the duration of unemployment in Eastern Germany. Based on administrative data for the time between the October 1999 and December 2002 of the Federal Employment Administration, we apply a bivariate mixed proportional hazards model. By doing so, we are able to use the information of the timing of treatment as well as observable and unobservable influences to identify the treatment effects. The results show that a participation in vocational training prolongates the unemployment duration in Eastern Germany. Furthermore, the results suggest that locking-in effects are a serious problem of vocational training programmes. JEL Classification: J64, J24, I28, J6

Sectoral heterogeneity in the employment effects of job creation schemes in Germany

Job creation schemes (JCS) have been one important programme of active labour market policy in Germany aiming at the re-integration of hard-to-place unemployed individuals into regular employment. In ontrast to earlier evaluation studies of these programmes based on survey data, we use administrative data containing more than 11,000 participants for our analysis and hence, can take effect heterogeneity explicitly into account. We focus on effect heterogeneity caused by differences in the implementation of programmes (economic sector, types of support and implementing institutions). The results are rather discouraging and show that in general, JCS are unable to improve the re-integration chances of participants into regular employment

New evidence on the effects of job creation schemes in Germany : a matching approach with threefold heterogeneity

This paper evaluates the effects of job creation schemes on the participating individuals in Germany. Since previous empirical studies of these measures have been based on relatively small datasets and focussed on East Germany, this is the first study which allows to draw policy-relevant conclusions. The very informative and exhaustive dataset at hand not only justifies the application of a matching estimator but also allows to take account of threefold heterogeneity. The recently developed multiple treatment framework is used to evaluate the effects with respect to regional, individual and programme heterogeneity. The results show considerable differences with respect to these sources of heterogeneity, but the overall finding is very clear. At the end of our observation period, that is two years after the start of the programmes, participants in job creation schemes have a significantly lower success probability on the labour market in comparison to matched non-participants. JEL Classification: H43, J64, J68, C13, C4

The employment effects of job creation schemes in Germany : a microeconometric evaluation

In this paper we evaluate the employment effects of job creation schemes on the participating individuals in Germany. Job creation schemes are a major element of active labour market policy in Germany and are targeted at long-term unemployed and other hard-to-place individuals. Access to very informative administrative data of the Federal Employment Agency justifies the application of a matching estimator and allows to account for individual (group-specific) and regional effect heterogeneity. We extend previous studies in four directions. First, we are able to evaluate the effects on regular (unsubsidised) employment. Second, we observe the outcome of participants and non-participants for nearly three years after programme start and can therefore analyse mid- and long-term effects. Third, we test the sensitivity of the results with respect to various decisions which have to be made during implementation of the matching estimator, e.g. choosing the matching algorithm or estimating the propensity score. Finally, we check if a possible occurrence of 'unobserved heterogeneity' distorts our interpretation. The overall results are rather discouraging, since the employment effects are negative or insignificant for most of the analysed groups. One notable exception are long-term unemployed individuals who benefit from participation. Hence, one policy implication is to address programmes to this problem group more tightly. JEL Classification: J68, H43, C1

Individual employment effects of job creation schemes in Germany with respect to sectoral heterogeneity

"Job creation schemes (JCS) have been one important programme of active labour market policy (ALMP) in Germany for a long time. They aim at the re-integration of hard-to-place unemployed into regular employment. A thorough microeconometric evaluation of these programmes was hindered by the fact, that the available (survey) datasets have been too small to account for a possible occurrence of effect heterogeneity. However, identifying effect heterogeneity can help to improve the design and implementation of future programmes. Hence, we use an administrative dataset of the Federal Employment Agency, containing over 11,000 participants to analyse the employment effects of JCS on an individual level. Whereas in a previous paper we analysed these effects with respect to group-specific and regional heterogeneity, we focus here explicitly on effect heterogeneity caused by differences in the implementation of programmes. In particular, we first evaluate the effects with respect to the economic sector in which the JCS are accomplished. Second, we analyse if different types of promotion lead to different effects. And finally we examine if there are varying effects which can be attributed to different implementing institutions. The results are rather discouraging and show that JCS are in general not able to improve the re-integration chances of participants into regular employment." (Author's abstract, IAB-Doku) ((en))IAB-Bewerberangebotsdatei, IAB-Maßnahmeteilnehmergrunddatei, Arbeitsbeschaffungsmaßnahme - Erfolgskontrolle, Wirkungsforschung, Wirtschaftszweige, Trägerschaft, berufliche Reintegration, Teilnehmer, beruflicher Verbleib, Geschlechterverteilung, Westdeutschland, Ostdeutschland, Bundesrepublik Deutschland

Pd nanoparticles confined in mesoporous N-doped carbon silica supports: a synergistic effect between catalyst and support

Palladium nanoparticles of similar size were deposited on different supports, layers of carbon materials (with and without nitrogen doping) on the surface of a MCF (mesocellular foam) silica. For the generation of the N-doped carbon coatings, three different N sources were used to also investigate a possible influence of the N-doped carbon precursor and thus the structure of the N-doped carbons on their performance as catalyst support. These catalysts were tested for the Suzuki coupling and hydrogenation reactions. For the Suzuki reaction, the carbon coatings showed to increase dramatically the stability of the MCF material. Furthermore, when N-doped carbon coatings were applied, strong improvement of the stability of the catalysts was observed due to an enhanced interaction between metal nanoparticles and the support, preventing metal particle growth. In hydrogenation reactions, the presence of the N-doped carbon coating on the silica support increases the adsorption of aromatic compounds causing an enhancement of the catalytic activity of Pd NPs when compared to the non-doped supports.TU Berlin, Open-Access-Mittel - 2020DFG, 390540038, EXC 2008: UniSysCa

The effects of short-term training measures on the individual unemployment duration in West Germany

Short-term training measures are the most important intervention of German active labor market policy in terms of persons promoted. However, evidence on the impacts of programs is missing. This study analyzes the effects of these programs on the individual unemployment duration in West Germany. By applying a multivariate mixed proportional hazards model, we are able to consider information of the timing of treatment in the unemployment spell as well as observable and unobservable factors to control for selectivity. Moreover, we allow treatment effects to vary over time and take account of heterogeneity in the effects due to individual differences. --Training Measures,Active Labor Market Policy,West Germany,Multivariate Mixed Proportional Hazards,Time-Varying Treatment Effects