Supercontinuum from Zr-EDF using Zr-EDF mode-locked fiber laser

Abstract

Abstract:We propose and demonstrate the generation of a supercontinuum (SC) spectrum from a 10 m long silica fiber co-doped with zirconia-yttria-alumino and erbium (Zr-EDF) as a non-linear medium. The proposed system utilizes a 2 m long Zr-EDF in a ring laser configuration to generate mode-locked pulses at 1560 nm based on the non-polarization rotation (NPR) technique. The fiber laser generates a mode-locking spectrum from 1526 to 1640 nm with a peak power of -10 dBm at approximately 1565 nm as well as a 6.1 nm bandwidth at the 3 dB level. The generated mode-locked pulses have average and peak powers of 15 mW and 1 kW respectively with a repetition rate of 23.2 MHz. These pulses are subsequently used to generate the SC spectrum from the 10 m Zr-EDF, with the SC spectrum obtained having a 200 nm bandwidth from 1500 nm as well as a large 3-dB bandwidth of 68.2 nm. The SC pulse width is 0.59 ps with a symmetrical shape at about 1600 nm and a 3-dB bandwidth of approximately 0.12 ps. This is the first report of a zirconia host employed as a non-linear medium for SC generation.

A hundreds of watt all-fiber near-infrared supercontinuum

“…Figure 3(a) shows the output spectrum after amplifier 3 under different average output powers. The mechanisms of spectral broadening are quite similar to those in [12,13]. With increase of the 976 nm pump power, the strong and coherent broadband 1064 nm signal after amplifier 2 works as the pump radiation of SRS, and lower order SRS acts as the pump source for higher order SRS, which keeps the spectrum broadening in the long wavelength direction.…”

“…We have achieved 70 and 177.6 W high power near-infrared SC in succession using this method, which proves its advantages in high power SC generation [14,15]. In this letter, the parameters of the nanosecond fiber laser seed and fiber amplifier are modified to overcome the gain saturation phenomenon in [13] and further scale the average output power of the near-infrared SC to 200 W. In addition, the roles of the peak power and the pulse width in the continuum formation are clarified in comparison experiments with different fiber laser seeds.…”

“…Recently, SC generation directly from a nonlinear fiber amplifier has attracted a lot of attention due to its simple structure and easy splicing, and some good results have been achieved at low average output power [9][10][11][12][13]. Stimulated Raman scattering (SRS) and soliton self-frequency shift (SSFS) are the main mechanisms in continuum formation, and the spectral broadening in the short wavelength direction is limited as a result of unmatched group velocity and phase.…”

Broadband supercontinuum generation with femtosecond pulse width in erbium-doped fiber laser (EDFL)

“…As previously explaned, this work employed a simple cavity seed laser of CNT-based SA passive ML technique to obtain a broader coverage of SC spectra compared to the reported work in [49] where the NPR technique is utilized as the seed laser before being amplified and launched into the dispersive media to induce the nonlinear effects. This NPR technique needs careful alignment of the light birefringence in the laser cavity and the stability of the pulse operation is sensitive to ambient fluctuation.…”

Experimental investigations of pulse shape control in passively mode-locked fiber lasers with net-normal dispersion

“…Because passively mode-locked fiber lasers have the capacity of emitting ps and fs pulses, they have attracted considerable interest for applications in ultrafast phenomena, nonlinear optics, and optical sensors [7][8][9][10][11]. Various kinds of modelocked fiber lasers have been proposed to achieve a diverse range of pulses [12][13][14][15]. According to the cavity design, laser oscillators can be divided into ring [16], figure of eight [17], gamma-shaped fiber lasers [18], and so on.…”