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Abstracts ved Netværk for Kvinder i Fysiks årsmøde 2001

High brightness broad area diode laser systems

Birgitte Thestrup


High power broad area laser (BAL) diodes are attractive laser sources for applications within the graphics industry and for medical applications due to their compactness and simplicity of operation. However, BAL diodes suffer from a poor spatial beam quality due to multimode lasing along the emitter stripe and this prohibits proper focusing of the laser beams and thus complicates coupling of the light into thin core fibres. A way to improve the spatial beam quality significantly and, thereby, the brightness of such lasers is to introduce optical feedback to the diodes in an external cavity by self-injection locking techniques.

In my presentation, I will give an introduction to high power BAL diodes and some of the feedback techniques, we use, such as off-axis self-injection locking and wavelength multiplexing by spectral beam combining. Both single and dual feedback schemes will be discussed. Some possible, promising applications of the laser sources with improved brightness will be introduced as well. I will present experimental results from external cavities for both single emitter and multi-emitter near-infrared BAL diodes and preliminary results from an external cavity for a diode laser bar. A recent initiative to improve the spatial, as well as, spectral coherence properties of a multi-emitter BAL diode involving phase conjugate mirror feedback will be introduced.

Pigerne, Naturvidenskaben og Gymnasiereformen

Jette Rygaard Poulsen

Frederikshavn Gymnasium og HF-kursus

Naturfag for alle og alligevel en styrkelse af det faglige niveau i naturvidenskab? Der stilles store krav til reformgymnasiet, og selvom den nye gymnasielov kun fejrer ét års fødselsdag, tegner der sig allerede et billede af hvad der, set fra naturvidenskabs side, er succes og hvad der kunne ønskes bedre. Rammerne for undervisning i de naturvidenskabelige fag i gymnasiet er bredere og væsentligt mere frie end tidligere, med plads til elevernes aktive medvirken og medbestemmelse. Til gengæld vil to tredjedele af eleverne gå igennem gymnasiet med et minimum af naturvidenskabelige fag. Og pigerne - hvilke muligheder giver gymnasiereformen for at støtte og udvikle deres interesse for naturvidenskab?

Playing with Molecular Footballs and other Fun Things: has being a woman helped or hindered?

Eleanor Campbell

Göteborg Universitet

I will talk about the exciting developments in the world of carbon nanoscience since the mid-eighties when the fullerenes were discovered. Five years after the initial discovery a method was found to make large quantities of purified C60 and C70 as well as carbon nanotubes thus opening up a new research area concerned with the study of the properties and potential applications of these new nanomaterials. I was lucky to become involved with research in fullerenes at a very early stage when it seemed that exciting new discoveries were being made almost on a daily basis. I will talk about the science but also give some reflections on my experiences as a woman and how this may or may not have affected my scientific career.