Sylvain Girard - Academia.edu (original) (raw)

Papers by Sylvain Girard

Research paper thumbnail of Watt-level deep-UV subnanosecond laser system based on Nd-doped fiber at 229 nm

Optics Letters, Feb 27, 2023

We report an efficient deep-UV master-oscillator power amplifier (MOPA) laser system at 229 nm th... more We report an efficient deep-UV master-oscillator power amplifier (MOPA) laser system at 229 nm that generates 350 ps pulses at 2 MHz repetition rate with an average power of 1.2 W. The use of a polarization-maintaining large mode area neodymium-doped fiber operating on the 4F3/2→4I9/2 transition allows high-power laser emission of up to 28 W near 915 nm in the sub-nanosecond regime with low spectral broadening. Two nonlinear frequency conversion stages (LBO + BBO crystals) in a single-pass configuration directly convert the IR laser emission to deep UV. This laser demonstrates the great potential of Nd3+-doped fiber lasers to produce high-power deep-UV emission.

Research paper thumbnail of Femtosecond all-PM Nd-doped fiber laser operated near 910nm

Laser Congress 2021 (ASSL,LAC), 2021

We report a MOPA laser system near 910nm employing Nd-doped PM-fibers and a SESAM for mode-lockin... more We report a MOPA laser system near 910nm employing Nd-doped PM-fibers and a SESAM for mode-locking. SPM-induced spectral broadening in a W-type Nd-doped fiber amplifier allows pulse recompression to 300fs and pulse energy of 11nJ.

Research paper thumbnail of 83 W efficient Nd-doped LMA fiber laser at 910 nm

Fiber Lasers XIX: Technology and Systems, 2022

Research paper thumbnail of Mode-locked all-PM Nd-doped fiber laser near 910  nm

Optics Letters, 2021

We present a compact passively mode-locked fiber laser emitting near 910 nm with an all-polarizat... more We present a compact passively mode-locked fiber laser emitting near 910 nm with an all-polarization-maintaining fiber laser architecture. The ring-cavity laser configuration includes a core-pumped neodymium-doped fiber as a gain medium and a semiconductor saturable absorber mirror as a passive mode-locking element. A bandpass filter is used to suppress parasitic emission near 1.06 µm and allows wavelength tuning between 903 and 912 nm. The laser operates in a highly stable and self-starting all-normal-dispersion regime with a minimum pulse duration of 8 ps at 28.2 MHz pulse repetition rate and 0.2 nJ maximum pulse energy. A single-pass amplifier stage increases the pulse energy up to 1.5 nJ, and pulse compression with a pair of gratings is demonstrated with nearly Fourier transform limited pulses.

Research paper thumbnail of Frequency-quadrupled Nd-doped fiber laser source in the deep-UV at 226 nm

Laser Congress 2020 (ASSL, LAC), 2020

We present the first demonstration of a laser source at 226nm based on the frequency-quadrupling ... more We present the first demonstration of a laser source at 226nm based on the frequency-quadrupling of an all-PM Nd-doped fiber laser. The DUV laser delivers 175mW of average power, 50ns pulse at 30kHz repetition rate.

Research paper thumbnail of Efficient pulsed Nd-doped fiber laser at 905 nm and frequency conversion to 452nm and 226nm

We present in this work, the development of a nanosecond pulsed Master-Oscillator Power-Amplifier... more We present in this work, the development of a nanosecond pulsed Master-Oscillator Power-Amplifier (MOPA) laser system near 905 nm based on the 3-level transition of Neodymium using a novel low NA polarization-maintaining Nd-doped silica fiber with a 30µm core and 130µm cladding. The MOPA delivered up to 24 W of average power (0.6 mJ energy per pulse) with good beam quality (M²~1.4). Cascaded LBO and BBO crystals are used respectively for second-harmonic generation and fourth-harmonic generation, giving respectively average output powers of 4.9W at 452nm (conversion efficiency of 20%) and 550mW at 226nm (conversion efficiency of 10%).

Research paper thumbnail of Large core, low-NA Neodymium-doped fiber for high power CW and pulsed laser operation near 900 nm

Laser Congress 2019 (ASSL, LAC, LS&C), 2019

13 W output power near 900 nm in CW laser regime (beam quality factor M2~1.2) and pulse energy of... more 13 W output power near 900 nm in CW laser regime (beam quality factor M2~1.2) and pulse energy of 0.54 mJ in actively Q-switched regime was obtained using 30-µm diameter core, low-NA (0.045) Neodymium-doped fiber.

Research paper thumbnail of High-power Nd-doped fiber lasers tunable from 872 to 936nm

Frontiers in Optics 2015, 2015

High-power and tunable operation of Nd-doped fiber lasers at wavelengths as short as 872nm is rep... more High-power and tunable operation of Nd-doped fiber lasers at wavelengths as short as 872nm is reported. Using a reflective VBG, we showed a narrow linewidth (~35pm) laser emission with a maximum output power of 22W.

Research paper thumbnail of CW and Q-switched tunable Neodymium fiber laser sources at short IR wavelengths near 900nm

Advanced Solid State Lasers, 2015

We report results on high-power and tunable three-level Nd-doped fiber lasers. Using a reflective... more We report results on high-power and tunable three-level Nd-doped fiber lasers. Using a reflective VBG, laser wavelengths as short as 872 nm are achieved in CW regime with a narrow linewidth of 35 pm.

Research paper thumbnail of Extended tunability of Nd-doped fiber lasers operating at 872–936  nm

Optics Letters, 2015

Efficient operation of an Nd-doped fiber laser operating in a wavelength-tunable configuration us... more Efficient operation of an Nd-doped fiber laser operating in a wavelength-tunable configuration using a volume Bragg grating (VBG) is reported in this Letter. A high-power operation on the 4F3/2-4I9/2 transition of Nd3+ at short wavelengths below 900 nm is demonstrated for the first time in silica fibers. A high-efficiency (47% laser conversion) output power up to 22 W and a narrow linewidth of 0.035 nm are achieved. This configuration is compared with a more conventional fiber laser setup using a bandpass filter and a highly reflective dichroic mirror.

Research paper thumbnail of All-fiber Yb-doped CW and pulsed laser sources operating near 980nm

Advances in Optical Materials, 2011

ABSTRACT We present a CW/pulsed master oscillator-power amplifier (MOPA) fiber source operating n... more ABSTRACT We present a CW/pulsed master oscillator-power amplifier (MOPA) fiber source operating near 980nm and based on an Yb-doped fiber pumped by a Nd-doped fiber laser at 930nm. Up to 2.1W was obtained in CW regime with a slope efficiency of 81%.

Research paper thumbnail of Near-field optical imaging of plasmonic devices using heterodyne optical feedback on Er doped DFB fiber laser

Frontiers in Optics 2011/Laser Science XXVII, 2011

Research paper thumbnail of 20 W continuous-wave cladding-pumped Nd-doped fiber laser at 910 nm

Optics Letters, 2013

We demonstrate a double-clad fiber laser operating at 910 nm with a record power of 20 W. Laser e... more We demonstrate a double-clad fiber laser operating at 910 nm with a record power of 20 W. Laser emission on the three-level scheme is enabled by the combination of a small inner cladding-to-core diameter ratio and a high brightness pump source at 808 nm. A laser conversion efficiency as high as 44% was achieved in CW operating regime by using resonant fiber Bragg reflectors at 910 nm that prevent the lasing at the 1060 nm competing wavelength. Furthermore, in a master oscillator power-amplifier scheme, an amplified power of 14.8 W was achieved at 914 nm in the same fiber.

Research paper thumbnail of Periodic variations in the wavelength distributions following photon interferences : analogy with electron interferences

Journal of Physics: Conference Series, 2012

Research paper thumbnail of Linearly-polarized pulsed Nd-doped fiber MOPA at 905 nm and frequency conversion to deep-UV at 226 nm

Optics Express, 2021

We present the first frequency-quadrupled linearly-polarized Q-switched neodymium-doped fiber las... more We present the first frequency-quadrupled linearly-polarized Q-switched neodymium-doped fiber laser generating > 500 mW average power at 226 nm. For this purpose, an amplified Q-switched oscillator using novel large-mode-area (LMA) fibers and generating up to 24 W average power (15 kW peak power) at 905 nm was developed. Two nonlinear frequency conversion stages using a LBO crystal for SHG and a BBO crystal for FHG generate respectively up to 4.9 W average power in the deep blue at 452 nm and a maximum of 510 mW average power in the deep ultra-violet (DUV) at 226 nm. Performance limitations and further improvements are discussed.

Research paper thumbnail of Amplification de l'effet Goos-H�nchen � la r�flexion totale sur une couche di�lectrique

Research paper thumbnail of Heterodyne detection device for imaging an object by re-injection

Research paper thumbnail of Intracavity four wave mixing using modulated optical feedback in a diode-pumped Nd:YVO<inf>4</inf> laser

2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC), 2011

ABSTRACT We demonstrate dynamical amplification of phase conjugation in the gain medium of a Nd3+... more ABSTRACT We demonstrate dynamical amplification of phase conjugation in the gain medium of a Nd3+:YVO4 laser via excitation of its relaxation oscillations. Enhancement up to +30 dB compared to classical homodyne approach is observed.

Research paper thumbnail of Optical Feedback on Erbium Doped Fibre Laser for Efficient Heterodyne SNOM Imaging Near 1.5μm

MRS Proceedings, 2009

Heterodyne optical feedback on a class B laser is investigated for Scanning Near field Optical Mi... more Heterodyne optical feedback on a class B laser is investigated for Scanning Near field Optical Microscopy (SNOM). All-fiberized set-up combining an Er-doped Distributed Feedback (DFB) fiber laser, a pair of pigtailed acousto-optics modulators (AOM) and a shear-force based scanning probe technique has been developed for the simultaneous observation of topography and evanescent light field on integrated optical devices. First demonstration of imaging using this technique is illustrated by characterizing the propagating modes into a rib waveguide at 1.54μm. Comparison between a theoretical model based on beam propagation mode (BPM) simulations and experimental measurements validates the results.

Research paper thumbnail of A 10 kHz Ce:LiSAF laser pumped by the sum-frequency-mixed output of a copper vapour laser

Optics Communications, 2001

Research paper thumbnail of Watt-level deep-UV subnanosecond laser system based on Nd-doped fiber at 229 nm

Optics Letters, Feb 27, 2023

We report an efficient deep-UV master-oscillator power amplifier (MOPA) laser system at 229 nm th... more We report an efficient deep-UV master-oscillator power amplifier (MOPA) laser system at 229 nm that generates 350 ps pulses at 2 MHz repetition rate with an average power of 1.2 W. The use of a polarization-maintaining large mode area neodymium-doped fiber operating on the 4F3/2→4I9/2 transition allows high-power laser emission of up to 28 W near 915 nm in the sub-nanosecond regime with low spectral broadening. Two nonlinear frequency conversion stages (LBO + BBO crystals) in a single-pass configuration directly convert the IR laser emission to deep UV. This laser demonstrates the great potential of Nd3+-doped fiber lasers to produce high-power deep-UV emission.

Research paper thumbnail of Femtosecond all-PM Nd-doped fiber laser operated near 910nm

Laser Congress 2021 (ASSL,LAC), 2021

We report a MOPA laser system near 910nm employing Nd-doped PM-fibers and a SESAM for mode-lockin... more We report a MOPA laser system near 910nm employing Nd-doped PM-fibers and a SESAM for mode-locking. SPM-induced spectral broadening in a W-type Nd-doped fiber amplifier allows pulse recompression to 300fs and pulse energy of 11nJ.

Research paper thumbnail of 83 W efficient Nd-doped LMA fiber laser at 910 nm

Fiber Lasers XIX: Technology and Systems, 2022

Research paper thumbnail of Mode-locked all-PM Nd-doped fiber laser near 910  nm

Optics Letters, 2021

We present a compact passively mode-locked fiber laser emitting near 910 nm with an all-polarizat... more We present a compact passively mode-locked fiber laser emitting near 910 nm with an all-polarization-maintaining fiber laser architecture. The ring-cavity laser configuration includes a core-pumped neodymium-doped fiber as a gain medium and a semiconductor saturable absorber mirror as a passive mode-locking element. A bandpass filter is used to suppress parasitic emission near 1.06 µm and allows wavelength tuning between 903 and 912 nm. The laser operates in a highly stable and self-starting all-normal-dispersion regime with a minimum pulse duration of 8 ps at 28.2 MHz pulse repetition rate and 0.2 nJ maximum pulse energy. A single-pass amplifier stage increases the pulse energy up to 1.5 nJ, and pulse compression with a pair of gratings is demonstrated with nearly Fourier transform limited pulses.

Research paper thumbnail of Frequency-quadrupled Nd-doped fiber laser source in the deep-UV at 226 nm

Laser Congress 2020 (ASSL, LAC), 2020

We present the first demonstration of a laser source at 226nm based on the frequency-quadrupling ... more We present the first demonstration of a laser source at 226nm based on the frequency-quadrupling of an all-PM Nd-doped fiber laser. The DUV laser delivers 175mW of average power, 50ns pulse at 30kHz repetition rate.

Research paper thumbnail of Efficient pulsed Nd-doped fiber laser at 905 nm and frequency conversion to 452nm and 226nm

We present in this work, the development of a nanosecond pulsed Master-Oscillator Power-Amplifier... more We present in this work, the development of a nanosecond pulsed Master-Oscillator Power-Amplifier (MOPA) laser system near 905 nm based on the 3-level transition of Neodymium using a novel low NA polarization-maintaining Nd-doped silica fiber with a 30µm core and 130µm cladding. The MOPA delivered up to 24 W of average power (0.6 mJ energy per pulse) with good beam quality (M²~1.4). Cascaded LBO and BBO crystals are used respectively for second-harmonic generation and fourth-harmonic generation, giving respectively average output powers of 4.9W at 452nm (conversion efficiency of 20%) and 550mW at 226nm (conversion efficiency of 10%).

Research paper thumbnail of Large core, low-NA Neodymium-doped fiber for high power CW and pulsed laser operation near 900 nm

Laser Congress 2019 (ASSL, LAC, LS&C), 2019

13 W output power near 900 nm in CW laser regime (beam quality factor M2~1.2) and pulse energy of... more 13 W output power near 900 nm in CW laser regime (beam quality factor M2~1.2) and pulse energy of 0.54 mJ in actively Q-switched regime was obtained using 30-µm diameter core, low-NA (0.045) Neodymium-doped fiber.

Research paper thumbnail of High-power Nd-doped fiber lasers tunable from 872 to 936nm

Frontiers in Optics 2015, 2015

High-power and tunable operation of Nd-doped fiber lasers at wavelengths as short as 872nm is rep... more High-power and tunable operation of Nd-doped fiber lasers at wavelengths as short as 872nm is reported. Using a reflective VBG, we showed a narrow linewidth (~35pm) laser emission with a maximum output power of 22W.

Research paper thumbnail of CW and Q-switched tunable Neodymium fiber laser sources at short IR wavelengths near 900nm

Advanced Solid State Lasers, 2015

We report results on high-power and tunable three-level Nd-doped fiber lasers. Using a reflective... more We report results on high-power and tunable three-level Nd-doped fiber lasers. Using a reflective VBG, laser wavelengths as short as 872 nm are achieved in CW regime with a narrow linewidth of 35 pm.

Research paper thumbnail of Extended tunability of Nd-doped fiber lasers operating at 872–936  nm

Optics Letters, 2015

Efficient operation of an Nd-doped fiber laser operating in a wavelength-tunable configuration us... more Efficient operation of an Nd-doped fiber laser operating in a wavelength-tunable configuration using a volume Bragg grating (VBG) is reported in this Letter. A high-power operation on the 4F3/2-4I9/2 transition of Nd3+ at short wavelengths below 900 nm is demonstrated for the first time in silica fibers. A high-efficiency (47% laser conversion) output power up to 22 W and a narrow linewidth of 0.035 nm are achieved. This configuration is compared with a more conventional fiber laser setup using a bandpass filter and a highly reflective dichroic mirror.

Research paper thumbnail of All-fiber Yb-doped CW and pulsed laser sources operating near 980nm

Advances in Optical Materials, 2011

ABSTRACT We present a CW/pulsed master oscillator-power amplifier (MOPA) fiber source operating n... more ABSTRACT We present a CW/pulsed master oscillator-power amplifier (MOPA) fiber source operating near 980nm and based on an Yb-doped fiber pumped by a Nd-doped fiber laser at 930nm. Up to 2.1W was obtained in CW regime with a slope efficiency of 81%.

Research paper thumbnail of Near-field optical imaging of plasmonic devices using heterodyne optical feedback on Er doped DFB fiber laser

Frontiers in Optics 2011/Laser Science XXVII, 2011

Research paper thumbnail of 20 W continuous-wave cladding-pumped Nd-doped fiber laser at 910 nm

Optics Letters, 2013

We demonstrate a double-clad fiber laser operating at 910 nm with a record power of 20 W. Laser e... more We demonstrate a double-clad fiber laser operating at 910 nm with a record power of 20 W. Laser emission on the three-level scheme is enabled by the combination of a small inner cladding-to-core diameter ratio and a high brightness pump source at 808 nm. A laser conversion efficiency as high as 44% was achieved in CW operating regime by using resonant fiber Bragg reflectors at 910 nm that prevent the lasing at the 1060 nm competing wavelength. Furthermore, in a master oscillator power-amplifier scheme, an amplified power of 14.8 W was achieved at 914 nm in the same fiber.

Research paper thumbnail of Periodic variations in the wavelength distributions following photon interferences : analogy with electron interferences

Journal of Physics: Conference Series, 2012

Research paper thumbnail of Linearly-polarized pulsed Nd-doped fiber MOPA at 905 nm and frequency conversion to deep-UV at 226 nm

Optics Express, 2021

We present the first frequency-quadrupled linearly-polarized Q-switched neodymium-doped fiber las... more We present the first frequency-quadrupled linearly-polarized Q-switched neodymium-doped fiber laser generating > 500 mW average power at 226 nm. For this purpose, an amplified Q-switched oscillator using novel large-mode-area (LMA) fibers and generating up to 24 W average power (15 kW peak power) at 905 nm was developed. Two nonlinear frequency conversion stages using a LBO crystal for SHG and a BBO crystal for FHG generate respectively up to 4.9 W average power in the deep blue at 452 nm and a maximum of 510 mW average power in the deep ultra-violet (DUV) at 226 nm. Performance limitations and further improvements are discussed.

Research paper thumbnail of Amplification de l'effet Goos-H�nchen � la r�flexion totale sur une couche di�lectrique

Research paper thumbnail of Heterodyne detection device for imaging an object by re-injection

Research paper thumbnail of Intracavity four wave mixing using modulated optical feedback in a diode-pumped Nd:YVO<inf>4</inf> laser

2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC), 2011

ABSTRACT We demonstrate dynamical amplification of phase conjugation in the gain medium of a Nd3+... more ABSTRACT We demonstrate dynamical amplification of phase conjugation in the gain medium of a Nd3+:YVO4 laser via excitation of its relaxation oscillations. Enhancement up to +30 dB compared to classical homodyne approach is observed.

Research paper thumbnail of Optical Feedback on Erbium Doped Fibre Laser for Efficient Heterodyne SNOM Imaging Near 1.5μm

MRS Proceedings, 2009

Heterodyne optical feedback on a class B laser is investigated for Scanning Near field Optical Mi... more Heterodyne optical feedback on a class B laser is investigated for Scanning Near field Optical Microscopy (SNOM). All-fiberized set-up combining an Er-doped Distributed Feedback (DFB) fiber laser, a pair of pigtailed acousto-optics modulators (AOM) and a shear-force based scanning probe technique has been developed for the simultaneous observation of topography and evanescent light field on integrated optical devices. First demonstration of imaging using this technique is illustrated by characterizing the propagating modes into a rib waveguide at 1.54μm. Comparison between a theoretical model based on beam propagation mode (BPM) simulations and experimental measurements validates the results.

Research paper thumbnail of A 10 kHz Ce:LiSAF laser pumped by the sum-frequency-mixed output of a copper vapour laser

Optics Communications, 2001