Ion engine thrust vector study, phase 2 Quarterly report

Performance prediction for expected thrust misalignment in electron bombardment ion thruste

Phonon-assisted decoherence in the production of polarization-entangled photons in a single semiconductor quantum dot

We theoretically investigate the production of polarization-entangled photons through the biexciton cascade decay in a single semiconductor quantum dot. In the intermediate state the entanglement is encoded in the polarizations of the first emitted photon and the exciton, where the exciton state can be effectively ``measured'' by the solid state environment through the formation of a lattice distortion. We show that the resulting loss of entanglement becomes drastically enhanced if the phonons contributing to the lattice distortion are subject to elastic scatterings at the device boundaries, which might constitute a serious limitation for quantum-dot based entangled-photon devices.Comment: 4 pages, 3 figure, to appear in Physical Review Letter

Ion engine thrust vector study

Probability of thrust vector misalignment in ion thrustor arra

Studies at Oyster Bay in Jamaica, West Indies. III. Measurements of underwater-sunlight spectra

Spectral distributions of ambient underwater sunlight in Oyster Bay, Falmouth Harbor, Jamaica, West Indies, have been measured during the diurnal rise in the stimulable bioluminescent intensity of the marine dinoflagellate, Pyrodinium bahamense. In addition to the changes in light intensity during this period, there are large changes in the relative spectral distributions, as functions of both time and depth in the Bay. The blue-to-red intensity ratios vary by factors of 10 to 100

Enhancing Technological Innovation with the Implementation of a Sustainable Manufacturing Community

AbstractThe global challenge of sustainable value creation can be coped with by raising human awareness about it all around the world. Increasing process effectiveness and efficiency in view of shrinking natural resources, increasing competitiveness and profitability by selling functionality and service instead of physical products give strategic references for the development of the so called sustainable manufacturing community (SMC). Ubiquitous application of modern information and communication technology (ICT) for shaping responsible global citizenship by knowledge transfer can expand learning and teaching productivity by magnitudes, can strengthen the leverage of help for self-help, can enable initiative and creativity for entrepreneurial approaches in the global village without losing local differentiation. Elements of an architecture for an SMC and the concrete case of smart wheel urban mobility with an outlook for an exemplary German Vietnamese collaboration perspective are considered

Guidelines for the Definition of Innovative Industrial Product-service Systems (PSS) Business Models for Remanufacturing

AbstractRemanufacturing represents a well-suited approach for sustainable development in environmental, economic and social dimensions. Product-service systems (PSS) are among the most important enabler for remanufacturing. Companies that remain owner of a product have an intrinsic motivation to design goods for longer lifecycles considering the possibility of remanufacturing the product or its parts after each use phase. In addition, as the end customer only uses the goods without having its ownership, the acceptance – and consequently the demand – for remanufactured goods is significantly improved. This paper presents guidelines for the definition of innovative business models for remanufacturing, utilizing both remanufacturing and PSS characteristics, and permitting the dissemination of knowledge needed for successful implementation within a company strategy and operations model. Focusing on industrial PSS, an illustrative application of the guidelines is demonstrated

Phonon-assisted transitions from quantum dot excitons to cavity photons

For a single semiconductor quantum dot embedded in a microcavity, we theoretically and experimentally investigate phonon-assisted transitions between excitons and the cavity mode. Within the framework of the independent boson model we find that such transitions can be very efficient, even for relatively large exciton-cavity detunings of several millielectron volts. Furthermore, we predict a strong detuning asymmetry for the exciton lifetime that vanishes for elevated lattice temperature. Our findings are corroborated by experiment, which turns out to be in good quantitative and qualitative agreement with theory