Supercontinuum generation in highly nonlinear fibers using amplified noise-like optical pulses

Abstract

Supercontinuum generation in a highly nonlinear fiber pumped by noise-like pulses from an erbium-doped fiber ring laser is investigated. To generate ultrabroad spectra, a fiber amplifier is used to boost the power launched into the highly nonlinear fiber. After amplification, not only the average power of the noise-like pulses is enhanced but the spectrum of the pulses is also broadened due to nonlinear effects in the fiber amplifier. This leads to a reduction of the peak duration in their autocorrelation trace, suggesting a similar extent of pulse compression; by contrast, the pedestal duration increases only slightly, suggesting that the noise-like characteristic is maintained. By controlling the pump power of the fiber amplifier, the compression ratio of the noise-like pulse duration can be adjusted. Due to the pulse compression, supercontinuum generation with a broader spectrum is therefore feasible at a given average power level of the noise-like pulses launched into the highly nonlinear fiber. As a result, supercontinuum generation with an optical spectrum spanning from 1208 to 2111 nm is achieved using a 1-m nonlinear fiber pumped by amplified noise-like pulses of 15.5 MHz repetition rate at an average power of 202 mW.

High energy noise-like pulsing in a double-clad Er/Yb figure-of-eight fiber laser

“…SC light can be generated using different methods and from different sources including continuous wave (CW) [32] or pulsed sources like short pulses [33], ultra-short pulses [34] and even NLPs [25,26,[35][36][37].…”

Multi-pulse operation of a dissipative soliton fibre laser based on nonlinear polarisation rotation

“…Because the peak output power decreases, nonlinear effects in the cavity are not strong enough to result in wave breaking. The laser operating in this regime can be amplified to serve as a pump to generate a supercontinuum [24,25].…”

Double-scale Pulses Generated by Mode-locked Fibre Lasers and Their Applications

“…Moreover, peak power of sub-pulses may far exceed the average peak power of the entire wave packet because of their short duration. It was also established that double-scale pulses feature comparatively high efficiency of non-linear interaction with the propagation medium in harmonic generation [8], Raman conversion [9] or super-continuum generation [10][11][12][13]. We analyse these and other promising applications of double-scale pulses in the following discussion.…”

“…Nevertheless, over recent years, this topic has been rapidly gaining popularity after the observation of double-scale pulses with relatively high energy in ultralong fibre lasers. Active research prompted by this discovery has shown that double-scale pulses may even be preferable in a number of applications, including non-linear frequency conversion, such as harmonic generation [8], Raman conversion [9] or super-continuum generation [10][11][12][13], as well as applications in imaging and sensing systems with high temporal and/or spatial resolution. It was furthermore demonstrated that generation of double-scale pulses in long lasers represents a remarkably multiform phenomenon encompassing many non-linear optical mechanisms, whose interaction may result in the emergence of diverse spatio-temporal coherent structures in laser radiation [14].…”