Publications (10)0 Total impact
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Conference Proceeding: Light Controlling Light in an Optical Fibre: From Very Slow to Faster-Than-Light Speed
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ABSTRACT: We demonstrate a method to achieve an extremely wide and flexible external control of the group velocity of signals as they propagate along an optical fibre. This control is achieved by means of the gain and loss mechanisms of stimulated Brillouin scattering in the fibre itself. Our experiments show that group velocities below 71,000 km/s on one hand, well exceeding the speed of light in vacuum on the other hand and even negative group velocities can readily be obtained with a simple benchtop experimental setup. Advanced schemes can be realized thanks to the extremely flexible possibility to shape the gain spectrum to make it optimized for applications. Ultra wide bandwidth, delaying with flat amplitude response and lower distortion were successfully demonstrated this way.Intelligent Signal Processing, 2007. WISP 2007. IEEE International Symposium on; 11/2007 -
Conference Proceeding: Flexible Slow and Fast Light in Optical Fibers
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ABSTRACT: A method to achieve an extremely wide and flexible control of the group velocity in an optical fiber using stimulated Brillouin scattering is presented. Group velocities below 71,000 km/s on one hand, well exceeding the speed of light in vacuum on the other hand and even negative group velocities can readily be obtainedLasers and Electro-Optics Society, 2006. LEOS 2006. 19th Annual Meeting of the IEEE; 11/2006 -
Article: Potentialities of slow and fast light in optical fibers
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ABSTRACT: The ubiquitous role of optical fibers in modern photonic systems has stimulated research to realize slow and fast light devices directly in this close-to-perfect transmission line. Recent progress in developing optically-controlled delays in optical fibers, operating under normal environmental conditions and at telecommunications wavelengths, has paved the way towards real applications for slow and fast light. Advanced schemes can be realized thanks to the extremely flexible possibility to shape the gain spectrum to make it optimized for applications. Ultra wide bandwidth, delaying with flat amplitude response and lower distortion were successfully demonstrated this way. -
Article: Light Controlling Light in an Optical Fibre: From Very Slow to Faster-Than-Light Speed
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Article: Zero-Gain Slow Light in Optical Fibres
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Article: Progress in Brillouin Slow Light and Its Impact in Fiber Sensing
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ABSTRACT: This paper reviews the major advances in Brillouin slow light devices along the last two years. We also focus on the positive and negative implications of this effect in the development of fiber sensors. -
Article: True Time Reversal via Dynamic Brillouin Gratings in Polarization Maintaining Fibers
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ABSTRACT: A novel technique to realize true time reversal of an optical signal, using dynamic Brillouin gratings in high-birefringence fibers, is proposed. A data sequence of optical pulses with 2-ns duration was efficiently time-reversed. -
Article: Slow light fiber systems in microwave photonics
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ABSTRACT: Slow light systems are particularly attractive for analog signal processing, since their inherent limitation to a delay-bandwidth product of 1 is less critical for analog systems such as those used in microwave photonics. We present here the implementation of two basic functions - phase shifting and true time delaying - fully optically controlled using stimulated Brillouin scattering in optical fibers. The combination of these two functions makes possible the implementation of true time delays without limitation on the microwave carrier frequency using the separate carrier tuning technique. This is illustrated by the implementation of the delaying system for the realization of a microwave tunable notch filter. -
Article: Ultra Wide Range Tunable Delay Line Using Dynamic Grating Reflectors in Optical Fibers
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ABSTRACT: We experimentally demonstrate a novel technique to realize a tunable delay line based on dynamic Brillouin gratings in a high birefringence fiber. A 8ns pulse signal is continuously delayed up to 184ns with minor distortion. -
Article: Recent progress towards centimetric spatial resolution in distributed fibre sensing
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ABSTRACT: Optical fibre sensors based on stimulated Brillouin scattering have now clearly demonstrated their excellent capability for long-range distributed strain and temperature measurements. The fibre is used as sensing element and a value for temperature and/or strain can be obtained from any point along the fibre. While classical configurations have practically a spatial resolution limited by the phonon lifetime to 1 meter, novel approaches have been demonstrated these past years that can overcome this limit. This can be achieved either by the prior activation of the acoustic wave by a long lasting pre-pumping signal, leading to the optimized configuration using Brillouin echoes, or by probing a classically generated steady acoustic wave using a ultra-short pulse propagating in the orthogonal polarization of a highly birefringent fibre. These novel configurations can offer spatial resolutions in the centimetre range, while preserving the full accuracy on the determination of temperature and strain.
