Search results for "PHASE MODULATION"
showing 10 items of 170 documents
Numerical Maps for Fiber Lasers Mode Locked with Nonlinear Polarization Evolution: Comparison with Semi-Analytical Models
2008
We have used a fully vectorial model based on two coupled nonlinear Schrodinger equations to study mode locking and pulse generation initiated and stabilized by nonlinear polarization evolution in a stretched pulse, double-clad, Yb-doped, fiber laser. The model takes explicitly into account gain saturation, finite amplification bandwidth, Kerr-induced self- and cross-phase modulations, group velocity dispersion, polarization control, and linear birefringence. Complete maps versus the orientation of intra-cavity wave-plates have been established. They comprise a large variety of pulse regimes that can be simply obtained by turning the intracavity wave-plate: stable single pulse per round tri…
Nonlinear spectral compression in optical fiber: A new tool for processing degraded signals
2017
International audience; We propose two new applications of the spectral focusing by self-phase modulation that occurs in a nonlinear optical fiber. We numerically show the possibility of using nonlinear spectral compression to improve the optical signal to noise ratio and mitigate the amplitude jitter of the signal pulses. We also demonstrate experimentally that use of spectral focusing in a combination with an external sinusoidal phase modulation achieves efficient suppression of coherent spectral background.
All-optical nonlinear simultaneous polarization and intensity regeneration of a 40-Gb/s telecommunication signal
2012
We experimentally report the simultaneous all-optical regeneration of the polarization state and the intensity profile of a 40 Gb/s Return-to-Zero telecommunication signal by means of Kerr effect occurring in a single segment of fiber.
Four-wave mixing process induced by a self-phase modulated pulse in a hollow core capillary
2021
International audience; <span class="markedContent" id="page11R_mcid8"><span style="left: 247.583px; top: 366.24px; font-size: 16.6667px; font-family: sans-serif;" role="presentation" dir="ltr"></span><span style="left: 253px; top: 366.24px; font-size: 16.6667px; font-family: sans-serif; transform: scaleX(0.941702);" role="presentation" dir="ltr">In this work, we investigate the modal </span><span style="left: 518.183px; top: 366.24px; font-size: 16.6667px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 519.8px; top: 366.24px; font-size: 16.6667px; font-family: sans-serif; transform: scaleX(0.958087);" role="presentation" dir="ltr">four wa…
All-fibered high-quality 28-GHz to 112 GHz pulse sources based on nonlinear compression of optical temporal besselons
2021
The generation of high quality pulse trains at repetition rates of several tens of GHz remains a crucial step for optical telecommunications, optical sampling or component testing applications. Unfortunately, the current bandwidth limitations of optoelectronic devices do not allow the direct generation of well-defined optical pulse trains with low duty cycles. An attractive solution is based on a direct temporal phase modulation that is then converted into an intensity modulation thanks to a dispersive element that imprints a spectral quadratic phase. Picosecond pulses at repetition rates of several tens of GHz have been successfully demonstrated [1] . However, this approach suffers from a …
Offsetting Self-Phase Modulation in Optical Fibre by Sinusoidally Time-Varying Phase
2018
We report on our recent experimental and theoretical results on the use of a sinusoidally time-varying phase to suppress undesirable self-phase modulation of optical pulses propagating in fibre-optic systems.
High-quality 10 and 20 GHz repetition rate optical sources based on the spectral phase tailoring of a temporal sinusoidal phase modulation
2019
International audience; We theoretically introduce and experimentally demonstrate a new approach to generate high-quality, high repetition-rate pulse trains. This method is based on a temporal sinusoidal phase modulation combined with a triangular spectral phase shaping. Experimental results validate the concept at repetition rates of 10 and 20 GHz.
Bistable Device based on the Kerr Effect in a Microfiber Resonator
2007
We propose a bistable device based on the Kerr effect in a microfiber resonator. Our simulations show that low switching powers (in the order of a few tens of mW) are expected with tellurite microfibers.
Mitigation of self-phase modulation by sinusoidally time varying phase
2018
The propagation of intense ultra-short optical pulses in a Kerr medium such as an optical fibre remains a critical issue for many optical systems. This is because the self-phase modulation (SPM) of the propagating pulse usually causes a severe broadening of the pulse spectrum that is typically accompanied by an oscillatory structure. Several strategies have been proposed and successfully deployed to counteract the deleterious effects of SPM in fiber-optic systems, including spatial or temporal scaling to reduce the impact of nonlinearity. Other approaches rely on the exploitation of the peculiar properties of parabolic shaped pulses and self-similar evolution. However, none of these last te…
All-optical measurement of residual chromatic dispersion and OSNR using self-phase modulation in optical fiber
2011
International audience; We describe a new all-fibered device providing high accuracy all-optical measurements of both optical signal to noise ratio and residual chromatic dispersion. Taking advantage of the self-phase modulation driven spectral evolution of pulses propagating in a highly non-linear medium, we have numerically and experimentally validated the benefits of using an anomalous dispersive fiber combined with a central spectral filtering.