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Luc Thévenaz

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Publications associées (373)

Genetic-optimised aperiodic code for distributed optical fibre sensors

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Simon Adrien Zaslawski, Zhisheng Yang, Jian Wu, Sheng Wang

Distributed optical fibre sensors deliver a map of a physical quantity along an optical fibre, providing a unique solution for health monitoring of targeted structures. Considerable developments over recent years have pushed conventional distributed sensor ...

Nature Research2020

Distributed and dynamic strain sensing with high spatial resolution and large measurable strain range

Luc Thévenaz, Zhisheng Yang, Li Zhang, Malak Mohamed Hossameldeen Omar Mohamed Galal

A distributed and dynamic strain sensing system based on frequency-scanning phase-sensitive optical time domain reflectometry is proposed and demonstrated. By utilizing an RF pulse scheme with a fast arbitrary waveform generator, a train of optical pulses ...

2020

Giant Brillouin amplification in gas using hollow-core waveguides

Luc Thévenaz, Flavien Gyger

We report a strong Brillouin amplification in gas using hollow-core fibers, exceeding by 6 times the gain in solid silica fibers. A novel fiber laser using Brillouin lasing in gas has been demonstrated. ...

Optical Society of America2020

Opto-mechanical cross-talk reduction in air-holes multicore fibers

Luc Thévenaz, Simon Adrien Zaslawski, Zhisheng Yang, Yun Fu

We report on the use of air-holes in multicore fibers to alleviate intercore perturbations induced by forward stimulated Brillouin scattering. Comparisons with conventional multicore fibers show significant improvement in terms of cross-talk reduction. ...

Optical Society of America2020

Intense Brillouin amplification in gas using hollow-core waveguides

Luc Thévenaz, Flavien Gyger

Among all the nonlinear effects stimulated Brillouin scattering offers the highest gain in solid materials and has demonstrated advanced photonics functionalities in waveguides. The large compressibility of gases suggests that stimulated Brillouin scat- te ...

Nature Publishing Group2020

Short spatial resolutions retrieval from a long pulse BOTDA trace

Luc Thévenaz, Simon Adrien Zaslawski, Zhisheng Yang, Sheng Wang

A novel, to the best of our knowledge, postprocessing technique is proposed to extract with a flexible and variable spatial resolution the information from Brillouin optical time-domain analyzers, obtained using a pulse longer than the acoustic settling ti ...

2020

Frequency scanned phase sensitive optical time-domain reflectometry interrogation in multimode optical fibers

Luc Thévenaz, Zhisheng Yang, Alejandro Dominguez Lopez

Standard multimode optical fibers normally support transmission over some 100 modes. Large differences in the propagation constant and the spatial distribution of distinct modes degrade the performance of phase-sensitive optical time-domain reflectometry m ...

AIP2020

On the 2D Post-Processing of Brillouin Optical Time-Domain Analysis

Luc Thévenaz, Simon Adrien Zaslawski, Zhisheng Yang

The benefits and limitations inherent to the 2D post-processing of measurements from Brillouin optical time-domain analyzers are investigated from a fundamental point of view. In a preliminary step, the impact of curve fitting on the precision of the estim ...

IEEE Institute of Electrical and Electronics Engineers2020

Giant Brillouin Amplification in Gases

Luc Thévenaz, Flavien Gyger

In our work, we used stimulated Brillouin scattering directly in the gas medium (such as air) filling a hollow-core fiber to realize a massive optical amplification, by a factor of 200,000. ...

2020

Nano-photonic Supercontinuum Based Mid-Infrared Dual-Comb Spectroscopy

Luc Thévenaz, Tobias Kippenberg, Camille Sophie Brès, Hairun Guo, Junqiu Liu, Wenle Weng

We demonstrate an approach to dual-comb spectroscopy, based on dispersion engineered and ultra-broadband supercontinuum generation in photonic integrated nonlinear waveguides, and driven by low-noise fiber-laser combs. Both technologies arc statc-of-the-ar ...

IEEE2020

Optical fibre sensing for fast hotspot detection in SFCLs

Bertrand Dutoit, Luc Thévenaz, Bertrand Dutoit, Arooj Akbar, Zhisheng Yang, Sheng Wang

The health monitoring of superconducting fault current limiters (SFCL) is important for their large-scale exploitation in HVDC grids protection. The intrinsic non-homogeneity of critical current along the superconductor length can cause localized points of ...

2020

Study on the signal-to-noise ratio of Brillouin optical-time domain analyzers

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Sheng Wang

The signal-to-noise ratio (SNR) of Brillouin optical time-domain analyzers (BOTDA) is modelled and experimentally validated, using direct detection with and without the use of optical pre-amplification. The behavior of SNR as a function of the Brillouin ga ...

2020

Spectral Properties of the Signal in Phase-Sensitive Optical Time-Domain Reflectometry with Direct Detection

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Xin Lu, Li Zhang

The spectral properties of the Rayleigh backscattered traces measured by a phase-sensitive optical time-domain reflectometer (øOTDR) with direct detection are theoretically and experimentally analyzed. The spectrum of the measured øOTDR signal is found to ...

IEEE Institute of Electrical and Electronics Engineers2020

Observation of Stimulated Brillouin Scattering in Silicon Nitride Integrated Waveguides

Luc Thévenaz, Rui Ning Wang, Flavien Gyger, Tobias Kippenberg, Junqiu Liu, Arslan Sajid Raja, Jijun He

Silicon nitride (Si3N4) has emerged as a promising material for integrated nonlinear photonics and has been used for broadband soliton microcombs and low-pulse-energy supercontinuum generation. Therefore, understanding all nonlinear optical properties of S ...

2020

Nanophotonic supercontinuum-based mid-infrared dual-comb spectroscopy

Luc Thévenaz, Tobias Kippenberg, Camille Sophie Brès, Wolfgang Hänsel, Hairun Guo, Junqiu Liu, Wenle Weng

High resolution and fast detection of molecular vibrational absorption is important for organic synthesis, pharmaceutical processes, and environmental monitoring, and is enabled by mid-infrared (mid-IR) laser frequency combs via dual-comb spectroscopy. Her ...

2020

Strain measurement of hydraulic turbine using distributed optical fiber sensor: a preliminary study

Luc Thévenaz, Can Yao, Pingyu Zhu

This paper demonstrates the feasibility and huge potential of applying distributed fiber optic sensing technologies to strain monitoring and failure predictions in hydraulic machinery, validated by a good match between experimental results and theoretical ...

Optical Society of America, 20202020

Observation of stimulated Brillouin scattering in silicon nitride integrated waveguides

Luc Thévenaz, Flavien Gyger, Tobias Kippenberg, Junqiu Liu, Arslan Sajid Raja, Jijun He

We report the first observation of backward stimulated Brillouin scattering in fully cladded Si3N4 waveguides. The intrinsic Brillouin gain at 25 GHz and the photoelastic constant are estimated to be 4 × 10−13 m/W and |p12| = 0.047 ± 0.004 respectively. ...

Optical Society of America2020

Distributed hydrostatic pressure measurement using phase OTDR in a highly birefringent photonic crystal fiber

Luc Thévenaz, Li Zhang

Although distributed fiber-optic sensing of axial strain and temperature is a well-established technique, there are almost no demonstrations of distributed hydrostatic pressure sensing. The main obstacle for such measurements is the low sensitivity to pres ...

IEEE Institute of Electrical and Electronics Engineers2019

Fiber Bragg grating-based thermometer for drill bit temperature monitoring

Luc Thévenaz, Kenny Hey Tow

The temperature measurement of a drill bit during an implantology drilling process is proposed by using a fiber Bragg grating fitted inside the drill bit. Due to the rotational nature of the drilling process, a free-space fiber-optic rotary joint is used f ...

2019

High-resolution distributed shape sensing using phase-sensitive optical time-domain reflectometry and multicore fibers

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Alejandro Dominguez Lopez

In this paper, a highly-sensitive distributed shape sensor based on a multicore fiber (MCF) and phase-sensitive optical time-domain reflectometry (φ-OTDR) is proposed and experimentally demonstrated. The implemented system features a high strain sensitivit ...

2019

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