Benoit Cadier - Academia.edu (original) (raw)

Papers by Benoit Cadier

Journal of the European Optical Society-Rapid Publications

A recent JEOS-RP publication proposed Comments about Dispersion of Light Waves, and we present he... more A recent JEOS-RP publication proposed Comments about Dispersion of Light Waves, and we present here complementary comments for birefringence dispersion in polarization-maintaining (PM) fibers, and for its measurement techniques based on channeled spectrum analysis. We start by a study of early seminal papers, and we propose additional explanations to get a simpler understanding of the subject. A geometrical construction is described to relate phase birefringence to group birefringence, and it is applied to the measurement of several kinds of PM fibers using stress-induced photo-elasticity, or shape birefringence. These measurements confirm clearly that the difference between group birefringence and phase birefringence is limited to 15–20% in stress-induced PM fibers (bow-tie, panda, or tiger-eye), but that it can get up to a 3-fold factor with an elliptical-core (E-core) fiber. There are also surprising results with solid-core micro-structured PM fibers, that are based on shape bire...

arXiv (Cornell University), Dec 9, 2021

Broadband wavelength tuneability can ensure a new level of versatility for laser systems and exte... more Broadband wavelength tuneability can ensure a new level of versatility for laser systems and extend areas of their applications. Principle limitations of achieving wide tuning wavelength ranges are generally defined by the spectral bandwidth of the gain and traditional tuneability techniques, relying on electrically controlled or bulk filters, reducing laser efficiency and generation stability. In this work, we present nearly 90 nm tuneability in ultrafast Tm-doped fibre laser within the span from 1873 to 1962 nm by implementing variable feedback for efficient control of the excitation level of the active medium and, hence, the gain spectrum. The highest laser efficiency is observed with 20% feedback, generating 580-fs soliton pulses at 1877 nm central wavelength with 1.5 nJ output pulse energy. By combining the nonlinear Shrödinger equation and population inversion rate equations for the gain medium, the developed numerical model helps to unveil nonlinear pulse evolution under the influence of dynamically varying gain spectrum. The resulting laser system presents a compact and straightforward approach to achieve laser generation with a broad range tuneability of wavelength and operation regimes, which is not impaired by the limitations on laser stability or power performance and can be translated to other wavelength ranges.

International audienceNous présentons une source laser monolithique en oscillateur unique, basée ... more International audienceNous présentons une source laser monolithique en oscillateur unique, basée sur le pompage bidirectionnel à 793 nm d'une fibre double gaine, dont le coeur est codopé aux ions de Tm 3+ , Ho 3+. Cette source émet jusqu'à 195 W à 2,09 µm en régime de fonctionnement continu, avec une qualité de faisceau proche de la limite de diffraction (M² = 1,08)

Journée du Club Optique et Micro-ondes (JCOM 2017), Jul 3, 2017

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Broadband wavelength tuneability can ensure a new level of versatility for laser systems and exte... more Broadband wavelength tuneability can ensure a new level of versatility for laser systems and extend areas of their applications. Principle limitations of achieving wide tuning wavelength ranges are generally defined by the spectral bandwidth of the gain and traditional tuneability techniques, relying on electrically controlled or bulk filters, reducing laser efficiency and generation stability. In this work, we present nearly 90 nm tuneability in ultrafast Tm-doped fibre laser within the span from 1873 to 1962 nm by implementing variable feedback for efficient control of the excitation level of the active medium and, hence, the gain spectrum. The highest laser efficiency is observed with 20% feedback, while 25% feedback enabled achieving the highest output energy of 1 nJ in 600-fs soliton pulses at 1877 nm central wavelength. By combining the nonlinear Schrödinger equation and population inversion rate equations for the gain medium, the developed numerical model helps to unveil nonl...

HAL (Le Centre pour la Communication Scientifique Directe), Jul 5, 2021

Nous présentons les premiers résultats obtenus dans le cadre d'un projet dont l'aboutissement est... more Nous présentons les premiers résultats obtenus dans le cadre d'un projet dont l'aboutissement est la fabrication d'une source laser monolithique en régime continu basée sur l'utilisation d'une fibre triple gaine dopée holmium émettant à 2,12 µm. En particulier, le développement de la source de pompe monolithique continue à 1940 nm est présenté.

Journée de l'Ecole Doctorale 3M 2018, Oct 29, 2018

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Laser Congress 2020 (ASSL, LAC), 2020

We report on a high efficiency (45%) single-oscillator monolithic Tm3+, Ho3+-codoped fiber laser ... more We report on a high efficiency (45%) single-oscillator monolithic Tm3+, Ho3+-codoped fiber laser emitting 195 W at 2.09 µm in CW mode of operation, with a beam quality near the diffraction limit (M2 = 1.08).

Optics Express, 2021

We present a bi-directionally 793-nm diode-pumped Tm3+, Ho3+-codoped silica polarization maintain... more We present a bi-directionally 793-nm diode-pumped Tm3+, Ho3+-codoped silica polarization maintaining double-clad all-fiber laser based on a single-oscillator architecture emitting 195 W at 2.09 µm in continuous wave mode of operation, with a beam quality near the diffraction limit (M2 = 1.08). The power scaling of the laser is only pump-power-limited in the range of the total available pump power (540 W).

Les lasers a fibre DFB bi-polarisation sont des sources heterodynes de choix pour les senseurs ou... more Les lasers a fibre DFB bi-polarisation sont des sources heterodynes de choix pour les senseurs ou la photonique microonde. Dans ce cadre, nous demontrons et etudions la stabilisation du battement a 1 GHz d'un laser DFB bifrequence au moyen d'une boucle de reinjection optique decalee en frequence. La largeur de la plage d'accrochage du battement sur un synthetiseur est proportionnelle au taux de reinjection. Le bruit de phase du battement stabilise est de –104 dBc/Hz a 1 kHz. Des simulations numeriques indiquent que la forte dissymetrie de la plage d'accrochage, observee experimentalement, peut s'expliquer par un couplage phase-amplitude important (α > 1).

We investigated the radiation hardening of optical fiber amplifiers operating in space environmen... more We investigated the radiation hardening of optical fiber amplifiers operating in space environments. Through a real-time analysis in active configuration, we evaluated the role of Ce in the improvement of the amplifier performance against ionizing radiations. Ce-codoping is an efficient hardening solution, acting both in the limitation of defects in the host glass matrix of RE-doped optical fibers and in the stabilization of lasing properties of the Er3+-ions. On the one hand, in the near-infrared region, radiation induced attenuation measurements show the absence of radiation induced P-related defect species in host glass matrix of the Ce-codoped active fibers; on the other hand, in the Ce-free fiber, the higher lifetime variation shows stronger local modifications around the Er3+-ions with the absence of Ce.

We show that the polarization modes of a dual-frequency fiber laser can be efficiently phase-lock... more We show that the polarization modes of a dual-frequency fiber laser can be efficiently phase-locked using optical frequency-shifted feedback, leading to a stable optically-carried microwave clock signal. We also show that a delay-induced instability, characterized by periodic pulses in the envelope of the beat-note signal, takes place inside the phase-locking range. This observation agrees with the prediction of a delayed rate equation model.

Dans le contexte de la photonique microonde, nous demontrons la stabilisation du battement d'... more Dans le contexte de la photonique microonde, nous demontrons la stabilisation du battement d'un laser a fibre DFB bifrequence a 1,5 µm. Un oscillateur opto-electronique (OEO) auto-reference a 1 GHz est realise au moyen d'une boucle de reinjection optique hybride. Le bruit de phase du battement stabilise est alors reduit d'environ 20 dB.

2021 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 2021

Optics Express, 2020

We report on our realization of a high-power holmium doped fiber laser, together with the validat... more We report on our realization of a high-power holmium doped fiber laser, together with the validation of our numerical simulation of the laser. We first present the measurements of the physical parameters that are mandatory to model accurately the laser-holmium interactions in our silica fiber. We then describe the realization of the clad-pumped laser, based on a triple-clad large mode area holmium (Ho) doped silica fiber. The output signal power is 90 W at 2120 nm, with an efficiency of about 50% with respect to the coupled pump power. This efficiency corresponds to the state of the art for clad-pumped Ho-doped fiber lasers in the 100 W power class. By comparing the experimental results to our simulation, we demonstrate its validity and use it to show that the efficiency is limited, for our fiber, by the non-saturable absorption caused by pair-induced quenching between adjacent holmium ions.

Optics Express, 2018

A fully fibered microwave-optical source at 1.5 µm is studied experimentally. It is shown that th... more A fully fibered microwave-optical source at 1.5 µm is studied experimentally. It is shown that the beat note between two orthogonally polarized modes of a distributed-feedback fiber laser can be efficiently stabilized using an optical phase-locked loop. The pump-powerinduced birefringence serves as the actuator. Beat notes at 1 GHz and 10 GHz are successfully stabilized to a reference synthesizer, passing from the 3 kHz free-running linewidth to a stabilized sub-Hz linewidth, with a phase noise as low as-75 dBc/Hz at 100 Hz offset from the carrier. Such dual-frequency stabilized lasers could provide compact integrated components for RF and microwave photonics applications.

Photoniques, 2019

Durant la dernière décennie, les besoins en fibres optiques et en capteurs à fibres optiques apte... more Durant la dernière décennie, les besoins en fibres optiques et en capteurs à fibres optiques aptes à opérer dans les environnements radiatifs les plus extrêmes ont connu une forte augmentation : pouvoir anticiper et/ou monitorer les conditions d’exploitation et leurs évolutions est devenu une absolue nécessité dans une multitude de domaines que sont l’espace, l’industrie nucléaire, le stockage des déchets radioactifs, ou encore la physique des hautes énergies et installations dévolues à l’étude de la fusion (Laser Mégajoule, ITER).

Optics Express, 2019

A bidirectional 793 nm diode-pumped actively Q-switched Tm 3+ , Ho 3+-codoped silica polarization... more A bidirectional 793 nm diode-pumped actively Q-switched Tm 3+ , Ho 3+-codoped silica polarization-maintaining (PM) double-clad (DC) fiber laser is reported. With this fiber laser, 55 W of average output power with 100 ns pulse width at 200 kHz repetition rate and 2.09 µm wavelength is obtained. The pump power injection with end-caps fusion-spliced on fiber tips provides good power stability (< 1.1%) and beam quality factors (M 2 < 1.7). The fiber laser output beam polarization factor is 97.5%. At 55 W, no thermal-induced damage is observed on any optical element, and power scaling of the laser is only pump-power-limited in the range of the total available pump power (180 W).

Optics Express, 2018

We present the first frequency-doubled neodymium-doped fiber laser generating multi-watt CW power... more We present the first frequency-doubled neodymium-doped fiber laser generating multi-watt CW power near 450 nm. A bow-tie resonator incorporating a LBO nonlinear crystal is integrated within a Nd-doped fiber laser emitting near 900 nm. This scheme achieves an IR to blue conversion efficiency close to 55% without any active control of the internal resonant cavity. As a result, up to 7.5 W of linearly-polarized blue power is generated, with beam quality factors M x 2 ~1.0 and M y 2 ~1.5. A simple numerical model has been developed to optimize and analyse the IR to blue conversion efficiency in the resonant cavity. Performance limitations and prospects for further improvements are discussed.

IEEE Transactions on Nuclear Science, 2018

Journal of the European Optical Society-Rapid Publications

A recent JEOS-RP publication proposed Comments about Dispersion of Light Waves, and we present he... more A recent JEOS-RP publication proposed Comments about Dispersion of Light Waves, and we present here complementary comments for birefringence dispersion in polarization-maintaining (PM) fibers, and for its measurement techniques based on channeled spectrum analysis. We start by a study of early seminal papers, and we propose additional explanations to get a simpler understanding of the subject. A geometrical construction is described to relate phase birefringence to group birefringence, and it is applied to the measurement of several kinds of PM fibers using stress-induced photo-elasticity, or shape birefringence. These measurements confirm clearly that the difference between group birefringence and phase birefringence is limited to 15–20% in stress-induced PM fibers (bow-tie, panda, or tiger-eye), but that it can get up to a 3-fold factor with an elliptical-core (E-core) fiber. There are also surprising results with solid-core micro-structured PM fibers, that are based on shape bire...

arXiv (Cornell University), Dec 9, 2021

Broadband wavelength tuneability can ensure a new level of versatility for laser systems and exte... more Broadband wavelength tuneability can ensure a new level of versatility for laser systems and extend areas of their applications. Principle limitations of achieving wide tuning wavelength ranges are generally defined by the spectral bandwidth of the gain and traditional tuneability techniques, relying on electrically controlled or bulk filters, reducing laser efficiency and generation stability. In this work, we present nearly 90 nm tuneability in ultrafast Tm-doped fibre laser within the span from 1873 to 1962 nm by implementing variable feedback for efficient control of the excitation level of the active medium and, hence, the gain spectrum. The highest laser efficiency is observed with 20% feedback, generating 580-fs soliton pulses at 1877 nm central wavelength with 1.5 nJ output pulse energy. By combining the nonlinear Shrödinger equation and population inversion rate equations for the gain medium, the developed numerical model helps to unveil nonlinear pulse evolution under the influence of dynamically varying gain spectrum. The resulting laser system presents a compact and straightforward approach to achieve laser generation with a broad range tuneability of wavelength and operation regimes, which is not impaired by the limitations on laser stability or power performance and can be translated to other wavelength ranges.

International audienceNous présentons une source laser monolithique en oscillateur unique, basée ... more International audienceNous présentons une source laser monolithique en oscillateur unique, basée sur le pompage bidirectionnel à 793 nm d'une fibre double gaine, dont le coeur est codopé aux ions de Tm 3+ , Ho 3+. Cette source émet jusqu'à 195 W à 2,09 µm en régime de fonctionnement continu, avec une qualité de faisceau proche de la limite de diffraction (M² = 1,08)

Journée du Club Optique et Micro-ondes (JCOM 2017), Jul 3, 2017

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Broadband wavelength tuneability can ensure a new level of versatility for laser systems and exte... more Broadband wavelength tuneability can ensure a new level of versatility for laser systems and extend areas of their applications. Principle limitations of achieving wide tuning wavelength ranges are generally defined by the spectral bandwidth of the gain and traditional tuneability techniques, relying on electrically controlled or bulk filters, reducing laser efficiency and generation stability. In this work, we present nearly 90 nm tuneability in ultrafast Tm-doped fibre laser within the span from 1873 to 1962 nm by implementing variable feedback for efficient control of the excitation level of the active medium and, hence, the gain spectrum. The highest laser efficiency is observed with 20% feedback, while 25% feedback enabled achieving the highest output energy of 1 nJ in 600-fs soliton pulses at 1877 nm central wavelength. By combining the nonlinear Schrödinger equation and population inversion rate equations for the gain medium, the developed numerical model helps to unveil nonl...

HAL (Le Centre pour la Communication Scientifique Directe), Jul 5, 2021

Nous présentons les premiers résultats obtenus dans le cadre d'un projet dont l'aboutissement est... more Nous présentons les premiers résultats obtenus dans le cadre d'un projet dont l'aboutissement est la fabrication d'une source laser monolithique en régime continu basée sur l'utilisation d'une fibre triple gaine dopée holmium émettant à 2,12 µm. En particulier, le développement de la source de pompe monolithique continue à 1940 nm est présenté.

Journée de l'Ecole Doctorale 3M 2018, Oct 29, 2018

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Laser Congress 2020 (ASSL, LAC), 2020

We report on a high efficiency (45%) single-oscillator monolithic Tm3+, Ho3+-codoped fiber laser ... more We report on a high efficiency (45%) single-oscillator monolithic Tm3+, Ho3+-codoped fiber laser emitting 195 W at 2.09 µm in CW mode of operation, with a beam quality near the diffraction limit (M2 = 1.08).

Optics Express, 2021

We present a bi-directionally 793-nm diode-pumped Tm3+, Ho3+-codoped silica polarization maintain... more We present a bi-directionally 793-nm diode-pumped Tm3+, Ho3+-codoped silica polarization maintaining double-clad all-fiber laser based on a single-oscillator architecture emitting 195 W at 2.09 µm in continuous wave mode of operation, with a beam quality near the diffraction limit (M2 = 1.08). The power scaling of the laser is only pump-power-limited in the range of the total available pump power (540 W).

Les lasers a fibre DFB bi-polarisation sont des sources heterodynes de choix pour les senseurs ou... more Les lasers a fibre DFB bi-polarisation sont des sources heterodynes de choix pour les senseurs ou la photonique microonde. Dans ce cadre, nous demontrons et etudions la stabilisation du battement a 1 GHz d'un laser DFB bifrequence au moyen d'une boucle de reinjection optique decalee en frequence. La largeur de la plage d'accrochage du battement sur un synthetiseur est proportionnelle au taux de reinjection. Le bruit de phase du battement stabilise est de –104 dBc/Hz a 1 kHz. Des simulations numeriques indiquent que la forte dissymetrie de la plage d'accrochage, observee experimentalement, peut s'expliquer par un couplage phase-amplitude important (α > 1).

We investigated the radiation hardening of optical fiber amplifiers operating in space environmen... more We investigated the radiation hardening of optical fiber amplifiers operating in space environments. Through a real-time analysis in active configuration, we evaluated the role of Ce in the improvement of the amplifier performance against ionizing radiations. Ce-codoping is an efficient hardening solution, acting both in the limitation of defects in the host glass matrix of RE-doped optical fibers and in the stabilization of lasing properties of the Er3+-ions. On the one hand, in the near-infrared region, radiation induced attenuation measurements show the absence of radiation induced P-related defect species in host glass matrix of the Ce-codoped active fibers; on the other hand, in the Ce-free fiber, the higher lifetime variation shows stronger local modifications around the Er3+-ions with the absence of Ce.

We show that the polarization modes of a dual-frequency fiber laser can be efficiently phase-lock... more We show that the polarization modes of a dual-frequency fiber laser can be efficiently phase-locked using optical frequency-shifted feedback, leading to a stable optically-carried microwave clock signal. We also show that a delay-induced instability, characterized by periodic pulses in the envelope of the beat-note signal, takes place inside the phase-locking range. This observation agrees with the prediction of a delayed rate equation model.

Dans le contexte de la photonique microonde, nous demontrons la stabilisation du battement d'... more Dans le contexte de la photonique microonde, nous demontrons la stabilisation du battement d'un laser a fibre DFB bifrequence a 1,5 µm. Un oscillateur opto-electronique (OEO) auto-reference a 1 GHz est realise au moyen d'une boucle de reinjection optique hybride. Le bruit de phase du battement stabilise est alors reduit d'environ 20 dB.

2021 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 2021

Optics Express, 2020

We report on our realization of a high-power holmium doped fiber laser, together with the validat... more We report on our realization of a high-power holmium doped fiber laser, together with the validation of our numerical simulation of the laser. We first present the measurements of the physical parameters that are mandatory to model accurately the laser-holmium interactions in our silica fiber. We then describe the realization of the clad-pumped laser, based on a triple-clad large mode area holmium (Ho) doped silica fiber. The output signal power is 90 W at 2120 nm, with an efficiency of about 50% with respect to the coupled pump power. This efficiency corresponds to the state of the art for clad-pumped Ho-doped fiber lasers in the 100 W power class. By comparing the experimental results to our simulation, we demonstrate its validity and use it to show that the efficiency is limited, for our fiber, by the non-saturable absorption caused by pair-induced quenching between adjacent holmium ions.

Optics Express, 2018

A fully fibered microwave-optical source at 1.5 µm is studied experimentally. It is shown that th... more A fully fibered microwave-optical source at 1.5 µm is studied experimentally. It is shown that the beat note between two orthogonally polarized modes of a distributed-feedback fiber laser can be efficiently stabilized using an optical phase-locked loop. The pump-powerinduced birefringence serves as the actuator. Beat notes at 1 GHz and 10 GHz are successfully stabilized to a reference synthesizer, passing from the 3 kHz free-running linewidth to a stabilized sub-Hz linewidth, with a phase noise as low as-75 dBc/Hz at 100 Hz offset from the carrier. Such dual-frequency stabilized lasers could provide compact integrated components for RF and microwave photonics applications.

Photoniques, 2019

Durant la dernière décennie, les besoins en fibres optiques et en capteurs à fibres optiques apte... more Durant la dernière décennie, les besoins en fibres optiques et en capteurs à fibres optiques aptes à opérer dans les environnements radiatifs les plus extrêmes ont connu une forte augmentation : pouvoir anticiper et/ou monitorer les conditions d’exploitation et leurs évolutions est devenu une absolue nécessité dans une multitude de domaines que sont l’espace, l’industrie nucléaire, le stockage des déchets radioactifs, ou encore la physique des hautes énergies et installations dévolues à l’étude de la fusion (Laser Mégajoule, ITER).

Optics Express, 2019

A bidirectional 793 nm diode-pumped actively Q-switched Tm 3+ , Ho 3+-codoped silica polarization... more A bidirectional 793 nm diode-pumped actively Q-switched Tm 3+ , Ho 3+-codoped silica polarization-maintaining (PM) double-clad (DC) fiber laser is reported. With this fiber laser, 55 W of average output power with 100 ns pulse width at 200 kHz repetition rate and 2.09 µm wavelength is obtained. The pump power injection with end-caps fusion-spliced on fiber tips provides good power stability (< 1.1%) and beam quality factors (M 2 < 1.7). The fiber laser output beam polarization factor is 97.5%. At 55 W, no thermal-induced damage is observed on any optical element, and power scaling of the laser is only pump-power-limited in the range of the total available pump power (180 W).

Optics Express, 2018

We present the first frequency-doubled neodymium-doped fiber laser generating multi-watt CW power... more We present the first frequency-doubled neodymium-doped fiber laser generating multi-watt CW power near 450 nm. A bow-tie resonator incorporating a LBO nonlinear crystal is integrated within a Nd-doped fiber laser emitting near 900 nm. This scheme achieves an IR to blue conversion efficiency close to 55% without any active control of the internal resonant cavity. As a result, up to 7.5 W of linearly-polarized blue power is generated, with beam quality factors M x 2 ~1.0 and M y 2 ~1.5. A simple numerical model has been developed to optimize and analyse the IR to blue conversion efficiency in the resonant cavity. Performance limitations and prospects for further improvements are discussed.

IEEE Transactions on Nuclear Science, 2018