Ingemar Petermann

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The blue OLED emission from a mobile phone was characterised, revealing a sharp emission band centred at λ = 445 nm with a 3dB bandwidth Δλ ∼ 20 nm. It was used to excite Rhodamine 123 doped within a "giant" mesostructured silica sphere during fabrication through evaporative self-assembly of silica nanoparticles. Fluorescence was able to be detected using a(More)
Elements heavier than iron are known to be made partly by the r-process, in a sequence of rapid neutron-captures and subsequent beta-decays in explosive scenarios with high neutron densities. Its astrophysical site has not yet been identified, despite the numerous works done in the last 50 years (see [2] for a review). We have studied systematically the(More)
We present a novel scheme based on sequential writing for fabrication of advanced fiber Bragg gratings. As opposed to earlier sequential methods this technique uses a cw UV laser source and allows for very precise control and repetitivity of the formation of the gratings. Furthermore it is possible to use high average irradiances without destroying the(More)
Different sources of stitch errors are identified and simulated in a 200 mm long chirped grating. In each case, the effect on the group-delay ripple and transmission spectrum is investigated. The anticipated response in a typical 10 Gbit/s transmission system is specifically considered. From the simulations, it is clear that information about error source(More)
We constructed a type of sensor by depositing a solgel layer within the interior holes of a silica-structured fiber and, subsequently, coating this with an acid-responsive porphyrin. Protonation of the porphyrin by an acidic gas (HCl in this case), is detected by a large change in the visible spectrum. Compared to previous work on a liquid-core sensor in a(More)
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