Thibault North

Raman-induced noiselike pulses in a highly nonlinear and dispersive all-fiber ring laser

Dual-wavelength noiselike pulses are generated in a fiber ring laser. A first series of pulses is induced at a wavelength of 1550 nm by the interplay of an erbium-doped fiber and nonlinear polarization rotation. From the Raman gain of these pump pulses emerges a second series of Stokes pulses at 1650 nm. With adequate control of the polarization states in the cavity, the noiselike Stokes pulses extend over 84 nm in the Ultralong-wavelengths band (U-band), while the pump pulses span over 46 nm.

Regenerative self-pulsating sources of large bandwidths

Self-pulsating sources based on cascaded regeneration by self-phase modulation and offset filtering are investigated experimentally using large filter bandwidths of 3.5 nm and up to semi-infinite bandwidths. In accordance with numerical results reported previously, such sources self-start from amplified spontaneous emission, and picosecond pulses are sustained in a nonlinear cavity. We provide numerical and experimental results indicating the generation of 2 ps pulses and observe 0.4 ps pulses after dispersion compensation and amplification. We also demonstrate that a pair of low- and high-pass filters spawn pulses whose bandwidths are determined by the combination of the filters and gain profiles, hence simplifying the experimental setup for short pulse generation.

Analysis of Self-Pulsating Sources Based on Regenerative SPM: Ignition, Pulse Characteristics and Stability

We provide design guidelines and resulting outputs of a self-pulsating source based on regenerative self-phase modulation and offset band-pass filtering. We assess the conditions for self-pulsation and discuss the output pulse properties under the influence of spectral separation between the filters and their bandwidth. We also examine the source behavior when the central wavelength of the bandpass filters are subject to increasing spectral separation in the pulse-buffering regime. The results emphasize the role of chromatic dispersion for the reduction of amplitude and timing jitter.

Fabrication and characterization of a pulsed fiber ring laser based on As 2 S 3

We demonstrate the operation of a fiber ring laser using a 19.5 cm segment of As2S3 chalcogenide fiber. The laser is passively mode-locked via nonlinear polarization rotation and provides two different operation regimes of picosecond and noiselike pulses. This ring configuration also enables an accurate measurement of the chromatic dispersion of the chalcogenide fiber.

Analysis of Self-Pulsating Sources Based on Cascaded Regeneration and Soliton Self-Frequency Shifting

We characterize the operation of self-pulsating sources made of two optical regenerators in cascade, namely a first regenerator of the type self-phase modulation spectral broadening and offset filtering, followed by a second regenerator of the type supercontinuum generation and offset filtering. The range of operation of this laser is explored as the wavelength and bandwidths of the band-pass filters are adjusted. We also provide experimental evidence that soliton self-frequency shift emanating from modulation instability triggers bursts of pulses at the repetition rate of the cavity. The stochastic nature of sources based on this concept leads to shot-to-shot pulse fluctuations in the cavity, which on average result in a flat supercontinuum extending beyond 1900 nm. Finally, a seed pulse can be sustained efficiently via this laser architecture, and the cavity consequently generates subpicosecond pulses at one of its output.

All-Optical Broadband Variable Optical Attenuator Based on an

We propose and demonstrate an all-optical broadband variable attenuator based on an As2Se3 microwire. The attenuation of the proposed fiber device as a function of the irradiating power is evaluated for the spectral regions of 1550 and 1850 nm, showing that photoinduced attenuation can be realized over a wide spectral range. We further assess the dynamic response of this variable attenuator upon modulating the amplitude of the irradiating beam.

{\rm As}_{2}{\rm Se}_{3}

We demonstrate experimentally and numerically the operation of a self-pulsating fiber laser based on the cascaded effects of soliton self-frequency shift and self-phase modulation spectral broadening. The combination of those two effects triggers and sustains the propagation of picosecond pulses in the cavity. At one of the outputs, the laser emits a supercontinuum with spectral width in excess of 150 nm at the repetition rate of 95 kHz.

Microwire

We report the first chalcogenide microwire that is designed with all-normal dispersion to generate supercontinuum by optical-wave-breaking, a low-noise nonlinear process. The generated supercontinuum spectrum spans over an octave from 960 nm to 2500 nm using a microwire length of only 3 mm.

Broadband self-pulsating fiber laser based on soliton self-frequency shift and regenerative self-phase modulation

We report on the operation of regenerative sources based on self-phase modulation (SPM) and soliton self-frequency shift (SSFS). Such stochastic sources generate a wide continuum spreading over 450 nm.

Broadband supercontinuum generation in all-normal dispersion chalcogenide microwires

We demonstrate the generation of dual-wavelength noiselike pulses in an Er3+ fiber laser. A ring cavity configu ration including a polarizer as saturable absorber induces a first series of pulses at the wavelength of 1550 nm via nonlinear polarization rotation. From the Raman gain of these pump pulses emerges a second series of Stokes pulses at 1650 nm. With an adequate control of the polarization states in the cavity, the Stokes pulses contain 67% of the total energy and reach a bandwidth of 84 nm in the U-band.