Spectrally Flat Supercontinuum Generation in a ZBLAN Fiber Pumped by Erbium-Doped Mode-Locked Fiber Laser

Huanhuan Liu,Tingyun Wang,Ye Yu,Qiao Jiang,Wei Song,Fufei Pang

doi:10.1007/s13320-019-0552-y

Abstract

We have experimentally demonstrated the flat supercontinuum (SC) generation using a 10-m-long ZrF4-BaF2-LaF3-AlF3-NaF (ZBLAN) fluoride fiber pumped by an erbium-doped mode-locked fiber laser incorporating carbon-nanotube-based saturable absorbers. In order to improve the spectral flatness of SC, the standardized single-mode fiber with different lengths is connected to the output of the mode-locked fiber laser before the pulse amplification. The generated SC with ZBLAN fiber exhibits the best spectral flatness with fluctuation less than 1.29dB over the wavelength of 1571.8nm–1803.1nm, showing potential applications in optical sensing.

Highlights

Supercontinuum (SC) laser sources with the ability to exhibit excellent wide bandwidth and good beam quality have attracted a significant scientific interest because of their wide applications covering the fields of metrology [1], molecular fingerprinting [2], infrared spectroscopy [3], as well as biomedicine [4]
We have demonstrated flat SC generation using a 10-m-long ZBLAN fiber pumped by a 1.5-μm mode-locked fiber laser incorporating carbon-nanotube-based saturable absorbers (CNTSAs)
The optimized seed light is amplified by an erbium-doped optical fiber amplifier (EDFA) and pumped into a 10-m-long single-mode ZBLAN fiber which has a core/clad diameter of 6/125 μm, a numerical aperture (NA) of 0.2, and a cut-off wavelength at 1650 nm

Summary

Introduction

Supercontinuum (SC) laser sources with the ability to exhibit excellent wide bandwidth and good beam quality have attracted a significant scientific interest because of their wide applications covering the fields of metrology [1], molecular fingerprinting [2], infrared spectroscopy [3], as well as biomedicine [4]. SC sources have potential applications in various long-distance optical sensing due to good beam profiles and high spectral stability [5]. Since Stolen and Lin observed SC generation in an optical fiber for the first time [6], various types of SC sources have been extensively investigated. Silica fibers have been the predominant nonlinear media of SC generation in the past decades due to their stability and low transmission loss in the visible and near-infrared regions [7]. Using silica fibers as the nonlinear medium of SC generation is affected by the strong intrinsic material losses in the long wavelength, which limits the spectral broadening towards mid-infrared (mid-IR) [2]. The ZDWs of chalcogenide fibers are usually above 4.5 μm [12], Article type: Regular

Methods

Results

Conclusion