Femtosecond seeding of a Tm-Ho fiber amplifier by a broadband coherent supercontinuum pulse from an all-solid all-normal photonic crystal fiber

Thulium-Holmium co-doped silica fiber amplifiers have a promising potential for femtosecond pulse amplification due to their broad gain bandwidth spanning from 1.7 to 2.2 μm, which could further support the growing application-driven demand for high peak power sub-100 fs pulse sources in this wavelength region. However, exploiting the full amplification bandwidth is limited mainly by a shortage of sufficiently broadband and coherent seed sources. The solitonic part of a supercontinuum (SC) generated by an Er:fiber femtosecond source in the anomalous dispersion region of a highly nonlinear fiber (HNF) has proven to be an effective seed source [1], but this approach requires careful management of the input pulse duration and HNF length to maintain coherence, and is intrinsically limited by the spectral bandwidth of the soliton.