781 research outputs found
Electromechanical wavelength tuning of double-membrane photonic crystal cavities
We present a method for tuning the resonant wavelength of photonic crystal
cavities (PCCs) around 1.55 um. Large tuning of the PCC mode is enabled by
electromechanically controlling the separation between two parallel InGaAsP
membranes. A fabrication method to avoid sticking between the membranes is
discussed. Reversible red/blue shifting of the symmetric/anti-symmetric modes
has been observed, which provides clear evidence of the electromechanical
tuning, and a maximum shift of 10 nm with < 6 V applied bias has been obtained.Comment: 9 pages, 3 figure
An AC electric trap for ground-state molecules
We here report on the realization of an electrodynamic trap, capable of
trapping neutral atoms and molecules in both low-field and high-field seeking
states. Confinement in three dimensions is achieved by switching between two
electric field configurations that have a saddle-point at the center of the
trap, i.e., by alternating a focusing and a defocusing force in each direction.
AC trapping of 15ND3 molecules is experimentally demonstrated, and the
stability of the trap is studied as a function of the switching frequency. A 1
mK sample of 15ND3 molecules in the high-field seeking component of the
|J,K>=|1,1> level, the ground-state of para-ammonia, is trapped in a volume of
about 1 mm^3
Size dependent exciton g-factor in self-assembled InAs/InP quantum dots
We have studied the size dependence of the exciton g-factor in self-assembled
InAs/InP quantum dots. Photoluminescence measurements on a large ensemble of
these dots indicate a multimodal height distribution. Cross-sectional Scanning
Tunneling Microscopy measurements have been performed and support the
interpretation of the macro photoluminescence spectra. More than 160 individual
quantum dots have systematically been investigated by analyzing single dot
magneto-luminescence between 1200nm and 1600 nm. We demonstrate a strong
dependence of the exciton g-factor on the height and diameter of the quantum
dots, which eventually gives rise to a sign change of the g-factor. The
observed correlation between exciton g-factor and the size of the dots is in
good agreement with calculations. Moreover, we find a size dependent anisotropy
splitting of the exciton emission in zero magnetic field.Comment: 15 pages, 7 figure
Entrepreneurship and well-being: the role of national entrepreneurship norm and the importance of meaningfulness at work
This study investigates whether entrepreneurship (operationalized as self-employment status) is related to higher levels of meaningfulness at work and individual’s well-being, specifically subjective vitality, when compared to regular employment. We propose that the impact of self-employment on meaningfulness at work would depend on countries’ normative context, namely on the national entrepreneurship prescriptive norm. We analysed 2010’s data from the Global Entrepreneurship Monitor and the European Social Survey on 16 European countries and tested a cross-level moderated mediation model. Results showed that entrepreneurship is positively related to individual’s well-being through the mediating effect of meaningfulness at work. However, the effect of entrepreneurship on individuals’ meaningfulness at work and, ultimately, on their subjective vitality, is stronger for people living in countries with less favorable national entrepreneurship norm. These findings provide evidence for framing meaningfulness at work as being contingent on the interaction between self-employment and national normative context and contribute to the literatures on entrepreneurship, meaningfulness, and well-being at workinfo:eu-repo/semantics/acceptedVersio
High-performance work systems and individual performance:A longitudinal study of the differential roles of happiness and health well-being
As a part of the growing strand of employee-centered HRM research, employee well-being is suggested to be a key mechanism that may help to explain the relationship between HRM and performance. To investigate how an employee’s well-being mediates the HRM-performance relationship, we distinguish between two types of well-being identified in prior work, happiness well-being and health well-being, and present arguments for differences in their effects on individual performance. Building on Job Demands-Resources (JDR) theory, we propose that happiness well-being positively mediates the relationship between perceived High-Performance Work Systems (HPWS) and individual task performance, while health well-being negatively mediates this focal relationship. Thus, happiness well-being fits the “mutual gains” perspective. In contrast, health well-being fits the “conflicting outcomes” perspective, and thus may be harmed by the HPWS to enhance the performance. We find partial support for our arguments in an analysis of longitudinal survey data of 420 participants spanning a total of four waves of data collection
Indium phosphide based membrane photodetector for optical interconnects on silicon
We have designed, fabricated and characterized an InP-based membrane photodetector on an SOI wafer containing a Si-wiring photonic circuit. New results on RF characterization up to 20 GHz are presented. The detector fabrication is compatible with wafer scale processing steps, guaranteeing compatibility towards future generation electronic IC processing
The influence of human resource practices on perceived work ability and the preferred retirement age: A latent growth modelling approach
Organisations are challenged to extend working lives of older workers. However, there is little empirical evidence available on how organisations should do this. This study aims to fill this gap by testing the effect of Human Resource (HR) practices on perceived work ability and the preferred retirement age. Based on the Conversation of Resources theory, we expected that the use of HR practices has a positive effect on perceived work ability and preferred retirement age. We have conducted latent growth curve modelling to test our hypotheses amongst 12,444 employees aged 45 and older at four time points. The results indicate that developmental practices are positively related to work ability, whereas maintenance practices are negatively related to work ability and the preferred retirement age. Accommodative practices are negatively related to the intercepts of both outcomes but not to the slopes, whereas utilisation practices are not related to the outcomes at all.publishedVersio
A linear AC trap for polar molecules in their ground state
Contains fulltext :
98810.pdf (preprint version ) (Open Access
Interventions for improving recovery from work
ObjectivesThis is a protocol for a Cochrane Review (intervention). The objectives are as follows:To compare the effectiveness of different individual interventions in recovery from work.info:eu-repo/semantics/publishedVersio
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