Optical charactcrisation of a Ncphila edulis spider dragline silk is performed. The silk fiber transmits light up to 1400 nm with a propagation loss of-9 dB/cm and birefringence of8xlO-3 measured at 1302 nm.
We experimentally demonstrate that structural slow light can enhance Beer-Lambert absorption. A 4-fold reduction of the group velocity induced by mere cavity effects has caused an increase of molecular absorption by 130%. Molecular absorption of gases is usually expressed by means of the Beer-Lambert law, stating that light transmitted though an absorbing… (More)
Global efforts made by the international community to reduce anthropogenic greenhouse gas emissions have not been successful yet to adequately address the challenge posed by climate change. On the contrary, global carbon emissions are still rising, raising the need to consider alternative backup options to mitigate global warming. Such solutions are known… (More)
PAR Isabelle DICAIRE ACKNOWLEDGEMENTS This thesis has been realised in the Group for Fibre Optics at EPFL under the supervision of Prof. Luc Thévenaz. First and foremost I wish to warmly thank him for allowing me to join his group and for believing in my abilities to do scientific research. He always welcomed my questions and helped me to improve my… (More)
High-resolution infrared absorption spectroscopy of acetylene gas is demonstrated in a dispersion-engineered photonic crystal waveguide under slow-light propagation. Experimental enhancement factors of 0.31 and 1.00 are obtained for TE and TM polarization, respectively, for group indices ranging from 1.5 to 6.7. The dependence of molecular absorption on the… (More)
Slowing light is expected to enhance light-matter interaction, leading to more compact sensing devices. By simple tests we show that the reality is more complex and the only relevant quantity is the wave electric field.
A couple of experiments are here presented to clarify the impact of slow light on light-matter interaction. The experiments are designed, so that the process generating slow light and the probed light-matter interaction only present a marginal cross-effect. The impact of slow light on simple molecular absorption could be separately evaluated under either… (More)
Deep Hα observations of the Sculptor Group galaxy NGC 7793 were obtained on the ESO 3.60m and the Marseille 36cm telescopes at La Silla, Chile. Hα emission is detected all the way to the edge of the H I disk, making of the H II disk of NGC 7793 one of the largest ever observed in a quiet non-AGN late– type system. Even in the very outer parts, the H II… (More)
Silk possesses extraordinary properties that scientists are currently working hard on harnessing. Amongst them, this primeval material has shown early potential of having excellent optical properties. Through a regeneration process, it is possible to obtain silk films made from fibres of silk cocoons, by casting a silk fibron solution on an appropriate… (More)
From the spider's perspective, silk is not only a building material but also a safety net, a weapon and a sensory organ to detect the presence of prey on its web. For scientists, dragline silk-directly extracted from spiders-is a tough, biodegradable and biocompatible optical fibre. These protein optical threads are made up of millions of repetitive protein… (More)