[show abstract][hide abstract] ABSTRACT: This work focuses on the influence of stress-rods on bending losses of polarization modes in microstructured optical fibers with large mode area. We perform detailed numerical simulations with a modal solver based on the finite element method that takes into account the stress distribution. We show that such fibers, in addition to guide a single-mode with a bending radius in the order of 10 cm, have a polarizing behavior as the losses of the fundamental mode along one of the propagation axis are strongly enhanced. A 50-µm core diameter LMA polarizing fiber was fabricated and characterized at 1064 nm.
Fiber Lasers XI: Technology, Systems, and Applications; 02/2014
[show abstract][hide abstract] ABSTRACT: The present work concerns the study of pulsed laser systems containing a
fiber amplifier for boosting optical output power. In this paper, this
fiber amplification device is included into a MOPFA laser, a master
oscillator coupled with fiber amplifier, usually a cladding-pumped
high-power amplifier often based on an ytterbium-doped fiber. An
experimental study has established that the observed nonlinear effects
(such as Kerr effect, four waves mixing, Raman effect) could behave very
differently depending on the characteristics of the optical source
emitted by the master laser. However, it has not yet been possible to
determine from the experimental data if the statistics of the photons is
alone responsible for the various nonlinear scenarios observed.
Therefore, we have developed a numerical simulation software for solving
the generalized nonlinear Schrödinger equation with a stochastic
source term in order to validate the hypothesis that the coherence
properties of the master laser are mainly liable for the behavior of the
observed nonlinear effects.
Contribution to the Topical Issue "Numelec 2012", Edited by Adel Razek.
The European Physical Journal Applied Physics 11/2013; 64(2):24506-. · 0.71 Impact Factor
[show abstract][hide abstract] ABSTRACT: For underwater surveillance applications, an all-optical acoustic array
technology allows enhanced capabilities compared to conventional
piezoelectric antenna in terms of compactness, robustness and large
distance remote interrogation through small diameter optical cable. This
paper presents the results obtained on a first full optical antenna
panel based on an innovative wideband pressure and temperature
compensated fiber laser hydrophone. The presented mock-up includes 12
fiber-laser optical hydrophones interrogated through a 4 km lead optical
[show abstract][hide abstract] ABSTRACT: We report for the first time a multiplexed array of 12 distributed
feedback fiber lasers (DFB FLs) on a single optical fiber, separated by
only 100 GHz (0.8 nm) in the C-band. These lasers are pumped by a 200 mW
laser diode at 1480 nm with no apparent impact on the sensor noise floor
despite the fact that the residual reflections from adjacent gratings
may be enhanced due to the smaller wavelength separation. Each DFB FL,
especially developed for serial multiplexing, exhibits low lasing
threshold typically between 1 and 2 mW, low intensity noise and very low
frequency noise (less than 30 dB re 1 Hz2/Hz at 1 kHz from optical
carrier). From these experimental results, extension to 32 DFB FLs array
(on 100 GHz ITU grid) multiplexed on one fiber will be discussed.
[show abstract][hide abstract] ABSTRACT: We report our developments of a 3-visible-wavelengths (Green, Yellow,
Red) CW fiber laser system providing more than 3W of output power per
colour on a single output path, in a simple and robust design. The
system is based on three infrared narrow linewidth linearly polarized
all-fiber lasers, combined into the same output PM fiber by a
fused-fiber PM multiplexer. This component has been specially developed
for the wavelengths of interest and to sustain high powers in CW
operation. The common polarized infrared output is sent into a non
linear optical stage to generate visible wavelengths, using
periodically-poled non linear crystals and single-pass frequency
doubling configuration. The system provides either 4W at 532 nm, 3W at
577 nm or 3.5W at 633 nm with a perfect beam quality and a free-space
[show abstract][hide abstract] ABSTRACT: In this paper, we present a complete overview of the optical and noise
performances of a high power single-frequency and single-mode fiber
laser system operating at 780 nm. It provides up to 1.8W of linearly
polarized output power at 780 nm, with 150 kHz linewidth and a perfect
diffraction limited Gaussian beam. This newly developed fiber laser
source is dedicated to trapping and cooling of Rb atoms for
Bose-Einstein condensation or gravimetric applications. A great
attention was paid to the laser intensity and frequency noises,
linewidth and beam characterization of this all-fiber system.
[show abstract][hide abstract] ABSTRACT: Presented is a new dual-frequency laser based on an erbium-doped distributed feedback fibre laser operating on two orthogonally polarised eigenstates around 1.55 μm, exhibiting a frequency offset in the micro-wave domain. The beatnote in the free running regime between these two optical waves allows the generation of an RF signal around 1 GHz with a RIN lower than - 115 dB/Hz over the frequency range 50 kHz to 10 MHz and a phase noise of -67 dBc/Hz at 10 kHz of the RF carrier. Up to 600 MHz tunability of the beatnote is obtained by mechanical stress applied to the cavity.
[show abstract][hide abstract] ABSTRACT: We present the full characterization of the beatnote of an erbium doped distributed feedback fiber laser (DFB-FL) operating on two orthogonally polarized eigenstates around 1.55 µm. The dual-frequency laser (DFL) in the free running regime generates a microwave signals around 1 GHz with a RIN lower than −115 dB/Hz over the range 50 kHz–10 MHz and a phase noise of −67 dBc/Hz at 10 kHz of the RF carrier. Up to 600 MHz tunability of the RF beatnote is obtained by mechanical stress applied to the cavity
[show abstract][hide abstract] ABSTRACT: We present in this paper second-harmonic generation (SHG) results of narrow-linewidth continuous-wave 1064 nm fiber lasers in periodically-poled crystals. We particularly compare SHG efficiencies that can be obtained in PPLN with single-frequency linearly-polarized fiber lasers and with narrow linewidth longitudinally multimode linearly-polarized fiber lasers. Both infrared lasers can provide around 4.5W at 1064nm. Due to the high number of modes, sum-frequencies between modes enhance the efficiency of multimode SHG by a factor of roughly 2 compared to single-frequency, but green generated radiation suffers from important intensity noise. Conversely, single-frequency SHG is less efficient, but intensity noise is greatly improved.
[show abstract][hide abstract] ABSTRACT: We demonstrate a simple method to measure the evolution of nonlinear effects along a pulse. An all-fiber acousto-optic modulator is synchronized to the pulse emission and inserted between the laser output and an optical spectrum analyzer. Thanks to this configuration, the application of a short modulator opening time (10 ns typically) compared to the pulse width (100 ns typically) forms a spectral measurement window. This window is shifted along the pulse by the use of a variable trig delay. The optical spectrum is measured for each position of the window. The nonlinear effects evolution versus the instantaneous power can be characterized. To validate our method, we have analyzed the spectral evolution along 100 ns pulses from different fiber laser sources. We have observed that the spectral broadening due to Kerr effect appears first. Raman scattering occurs next for window positions corresponding to highest peak powers. Finally during the trailing edge course, nonlinear effects disappear in the reverse order of their apparition. This method has also been extended to measure the power inside and outside a pulse in order to deduce the rate of amplified spontaneous emission.
[show abstract][hide abstract] ABSTRACT: We present in this paper multi-watts CW operation of an Ytterbium-doped fiber laser directly emitting at wavelengths above 1150 nm for frequency-doubling in the yellow spectral range. A maximum output power of more than 15W has been obtained at 1154 nm in CW linearly polarized operation with a linewidth of less than 0.20 nm (FWHM) in an all-fiber configuration. Multi-watts second-harmonic generation (SHG) in the yellow spectral range with periodically-poled non linear crystals is presented.
[show abstract][hide abstract] ABSTRACT: We study the impact of standard active double-clad (DC) fiber characteristics and laser architectures on the generation of long-wavelength Yb-doped high-power fiber lasers around 1154 nm. Both theoretical and experimental works have been performed highlighting that Yb-doped fiber lasers can emit efficiently in multiwatts operation at wavelengths higher than 1150 nm. This study has been focused on the use of standard all-fiber active and passive components as well as on the use of standard DC Yb-doped fibers without any spectral filtering except cavity mirrors.
IEEE Journal of Selected Topics in Quantum Electronics 02/2009; · 4.08 Impact Factor
[show abstract][hide abstract] ABSTRACT: In this paper, we have demonstrated all-fiber Q-switched cavities optimized for short and smooth output pulse generation. The great efficiency of small core diameter fibers allows reaching short pulses without using high pump power, preserving the setup simplicity of low power single transverse mode cavities.
[show abstract][hide abstract] ABSTRACT: Photonic-bandgap fibers (PBGF) are suitable for Raman-free propagation due to their intrinsic spectral filtering properties. The use of an all-solid PBGF for Raman filtering has been demonstrated. In this paper, we focus on the design of all-solid PBGFs for Raman-free propagation, and evaluate their performance by using an efficient spectrally-resolved model which has recently been developed.
[show abstract][hide abstract] ABSTRACT: We propose and demonstrate two methods for modal decomposition in multi-mode fibres. Linearly polarized modes propagating in a slightly multi-mode fibre are easily retrieved from intensity measurements at the fibre output surface. The first method is an improvement of the so-called spectrally and spatially imaging technique, which is limited to largemode- area optical fibers. The second method is a new, simpler and faster solution for the characterization of any kind of optical fibre, thus attractive in comparison to previously reported methods, which are cumbersome, time-consuming and/or limited to large-more-area fibres. Different kinds of multi-mode optical fibres are characterized. A large-modearea photonic-bandgap fibre, a photonic-crystal small-core non-linear fibre, and a standard index-stepped multi-mode fibre are characterized successfully.
[show abstract][hide abstract] ABSTRACT: It has come to the attention of the Optical Society of America that this article should not have been submitted owing to its substantial replication, without appropriate attribution, of significant elements found in the following previously published material: A. Crunteanu, D. Bouyge, D. Sabourdy, P. Blondy, V. Couderc, L. Grossard, P. H. Ploger and A. Barthelemy, "Deformable micro-electromechanical mirror integration in a fibre laser Q-switched system," J. Opt. A: Pure Appl. Opt. 8 S347-S351 (2006).
In this paper, active Q-switching of a double clad codoped erbium-Ytterbium fiber laser using a deformable metallic micro-mirror system is demonstrated. The electrostatically actuated micro-mirror acts both as the end laser cavity reflector and as switching/modulator element. When actuated, its shape changes from planar to a concave curvature, allowing control of the Q-factor of the laser cavity. The mirror/switching element is small, compact, highly reflective and achromatic, with a great integration potential. The laser system operates at frequencies between 20 and 200 kHz and generates short pulses (FWHM down to 300 ns) and high peak powers.
[show abstract][hide abstract] ABSTRACT: A new tuning configuration for dispersion compensating fibre Bragg gratings is presented. It allows a wide tuning range from -400 to +400 ps/nm without insertion loss variation and is suitable for 40 Gbit/s WDM systems.