We experimentally find a practical stimulated Brillouin scattering (SBS) threshold for broadband high-performance fiber optical parametric devices relying on dispersion-stable GeO2-doped silica highly nonlinear fibers. We demonstrate that SBS limits the nonlinear phase shift in such fibers to ~0.3 rad per pump unless the SBS is mitigated in some way. We consequently derive corresponding limits on signal gain and conversion efficiency and find the required SBS mitigation factor for a range of fiber optic parametric devices’ applications. Finally, we examine the level of SBS mitigation using air gaps and fiber tapers for implementation in polarization-insensitive fiber optic parametric devices employing bidirectional loops. We observe that an air gap or fiber taper are not very efficient for SBS mitigation as they provided an increase in SBS threshold up to 0.7 dB attributed primarily to their excess loss.
Bibliographical note© 2021 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Funding: This work was supported in part by the UK Engineering and Physical Sciences Research Council grants EP/ R024057/1 (FPA-ROCS), EP/M005283/1 (UPON) and EP/S003436/1 (PHOS) as well as by the European Commission Marie-Curie Multiply project OPERNET. The data reported in this paper is available as part of the UK EPSRC open access policy at https://researchdata.aston.ac.uk/ 491/.
- Fiber optical parametric amplification
- Wavelength conversion
- Optical phase conjugation
- Stimulated Brillouin scattering