Publications by Luc Thévenaz | EPFL Graph Search

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Brillouin distributed optical fibre sensing has been a subject of intense research and industrial development for more than twenty years, demonstrating its capabilities to be an effective and powerful measurement tool for a wide range of applications. Making use of sophisticated implementations, remarkable progresses on the sensing performance have been reported in the last decade, allowing significant improvements in spatial resolution and sensing range. However, the demand for distributed sensors with mor

We propose a novel configuration for a Brillouin distributed sensor based on Brillouin optical time domain analysis. This new configuration eliminates many intensity noise issues found in previous schemes. Resolution of 3.5 m all over a 47km single-mode fibre was achieved and resolution down to 30 cm in a few kilometre fibre. Noise reduction makes possible measurements with a 16 times averaging.

A multi-gas photoacoustic sensor is reported. Simultaneous measurement of ammonia, carbon dioxide and water vapor is demonstrated at ppm level using semiconductor lasers. In-situ measurements to control the housing conditions of laboratory animals are pres ...

A dynamically reconfigurable Microwave Photonic Filter based on True Time Delay generated by Stimulated Brillouin Scattering in optical fibers and separate phase shift of the optical carrier has been experimentally demonstrated, resulting in a flexible tun ...

According to the present invention there is provided methods of performing a distributing sensing measurement, comprising the steps of, modulating the frequency of one or more light signals output from one or more light sources, using one or more multi-lev ...

We describe some interesting features that arise when slow and fast light structures are introduced in interferometers. With different configurations, one can obtain a spectral sensitivity enhancement of the interferometer or an enhanced robustness to lase ...

Distributed temperature sensing with 10 dB back-reflection-enhanced fiber is performed based on φ-OTDR. While the temperature sensitivity of such fibers is similar to that of standard single-mode fibers, a 3-times higher temperature resolution is observed. ...

A differential pulse-width pair (DPP) Brillouin distributed fiber sensor is implemented to achieve centimetric spatial resolution over distances of several kilometers. The presented scheme uses a scanning method in which the spectral separation between the ...

The polarization evolution of stimulated Brillouin scattering amplified signals in the presence of fiber birefringence is examined in analysis, simulation and experiment. The signal polarization is drawn towards the conjugate of the pump polarization. ...

A novel distributed fibre sensing technique is described and experimentally validated, based on birefringence measurements using coherent Rayleigh scattering. It natively provides distributed measurements of temperature and strain with more than an order o ...

Energy transfer between the interacting waves in a distributed Brillouin sensor can result in a distorted measurement of the local Brillouin gain spectrum, leading to systematic errors. It is demonstrated that this depletion effect can be precisely modelle ...

Brillouin optical time-domain reflectometry is used to perform distributed forward stimulated Brillouin scattering (FSBS) measurements. This configuration suppresses the need for an additional frequency scanning to evaluate the local Brillouin peak gain wh ...

In this paper we demonstrate a long-range distributed strain and temperature optical fiber sensor using Brillouin optical time-domain analysis in conjunction with optical pulse coding. Compared to standard BOTDA, pulse coding provides higher signal-to-nois ...

Injection locking of two DFB semiconductors opens new possibilities to generate effective signals for fibre sensing. This is illustrated through the application to distributed Brillouin sensing that shows significant progress with respect to established techniques.

We demonstrate the generation of slow and fast light based on stimulated Brillouin scattering in As2Se3 chalcogenide fiber with the best efficiency ever reported. The Brillouin gain of 43 dB is achieved with only 60-mW pump power in a 5-m single-mode chalc ...

A novel concept for distributed fiber sensing has recently been introduced, in which the sensing fiber itself forms a laser cavity. This configuration yields a high-quality response that is largely independent of position, thereby enhancing measurement accuracy and acquisition speed, and opening new avenues towards higher-performance sensing technologies.

A comprehensive overview is presented about optical fiber-based tunable photonic delay lines, which have been steadily developed over the last decade for the realization of all-optically controlled timing functions. The most widely used techniques, such as ...

The Brillouin frequency shift and linewidth were measured over the full temperature range in which the fibre experiences no structural damage, demonstrating that Brillouin sensing can be actually performed from 1 K to 1000 K.

By analyzing the fundamentals of the operation of Brillouin sensors it will be shown that all efforts must be focused on obtaining the largest signal-to-noise ratio on the raw optical signal, which ultimately scales all performance of the sensor. Guideline ...

Luc Thévenaz

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Going beyond limits in Brillouin distributed fibre sensors: Challenges and possible approaches

High performance Brillouin distributed fibre sensor

Continuous and simultaneous multigas monitoring using a highly sensitive and selective photoacoustic sensor

True Time Delay on tunable Microwave Photonic Filter based on Stimulated Brillouin Scattering in fibers

Sensing systems and methods for distributed Brillouin sensing

How to play with the spectral sensitivity of interferometers using slow light concepts and how to do it practically

Distributed Temperature Sensing Based on φ-OTDR Using Back-reflection-enhanced Fiber

Resolving 1 million sensing points in an optimized differential time-domain Brillouin sensor

Polarization Evolution of Stimulated Brillouin Scattering Amplified Signals in Standard Fibers

Novel technique for distributed fibre sensing based on coherent Rayleigh scattering measurements of birefringence

Effect of pulse depletion in a Brillouin optical time-domain analysis system

Distributed forward stimulated Brillouin scattering measurement using broadband BOTDR

Distributed strain and temperature sensing over 50 km of SMF with 1 m spatial resolution employing BOTDA and optical pulse coding

Novel configurations based on laser injection locking applied to Brillouin fibre sensing

Highly efficient Brillouin slow and fast light using As2Se 3 chalcogenide fiber

Towards lasing systems for distributed fibre sensing

Kerr effect in structured superluminal media

Brillouin gain spectrum characterization in optical fibres from 1 to 1000 K

Brillouin distributed fiber sensors: Practical limitations and guidelines for the making of a good sensor

A High-Performance Optical Time-Domain Brillouin Distributed Fiber Sensor