Basic opto-electronics on silicon for sensor applications

A general platform for integrated opto-electronic sensor systems on silicon is proposed. The system is based on a hybridly integrated semiconductor laser, ZnO optical waveguides and monolithic photodiodes and electronic circuiry

A muon-track reconstruction exploiting stochastic losses for large-scale Cherenkov detectors

IceCube is a cubic-kilometer Cherenkov telescope operating at the South Pole. The main goal of IceCube is the detection of astrophysical neutrinos and the identification of their sources. High-energy muon neutrinos are observed via the secondary muons produced in charge current interactions with nuclei in the ice. Currently, the best performing muon track directional reconstruction is based on a maximum likelihood method using the arrival time distribution of Cherenkov photons registered by the experiment\u27s photomultipliers. A known systematic shortcoming of the prevailing method is to assume a continuous energy loss along the muon track. However at energies >1 TeV the light yield from muons is dominated by stochastic showers. This paper discusses a generalized ansatz where the expected arrival time distribution is parametrized by a stochastic muon energy loss pattern. This more realistic parametrization of the loss profile leads to an improvement of the muon angular resolution of up to 20% for through-going tracks and up to a factor 2 for starting tracks over existing algorithms. Additionally, the procedure to estimate the directional reconstruction uncertainty has been improved to be more robust against numerical errors

Hybride laser/chip-koppeling voor coherente ontvanger

Door ontwikkelingen als de digitale (high definition) televisie zal de behoefte aan breedbandig datatransport sterk toenemen. Optische communicatie is bij uitstek geschikt om deze functie te vervullen. Het Fysisch en Elektrontsch Laboratorium TNO (FEL-TNO) draagt door onderzoek naar de koppeling van een laser en een optische schakeling bij aan de ontwikkeling van een geintegreerde optische ontvanger voor coherente communicatie. De laser fungeert Ìn de ontvanger als lokale oscillator, een component nodig voor coherente detectie