Ultra-broadband supercontinuum(SC)lasers covering the mid-infrared(MIR)region have significant applications in trace substance detection,national defense,and biomedical fields.Currently,high-power SC spanning2–5μm i...Ultra-broadband supercontinuum(SC)lasers covering the mid-infrared(MIR)region have significant applications in trace substance detection,national defense,and biomedical fields.Currently,high-power SC spanning2–5μm is still dominated by traditional fluoride(InF_(3))fibers.Although tellurite fibers,with their excellent chemical and thermal stability,have demonstrated significantly higher power scalability compared to other MIR fibers,their spectral broadening capabilities in the 4–5μm region remain largely unexplored.Here,we demonstrate a>10 W ultra-broadband flat SC spanning the 1.8–5.1μm spectral range in a fluorotellurite fiber using a cascaded soliton self-frequency shifting technique.The fluorotellurite fiber is precisely tapered to reconstruct dispersion and nonlinearity,which facilitates the evolution of the pre-stage Raman soliton into higherorder solitons,thereby enabling a new round of“rapid relay fission.”At a low pump power of 7.5 W,we also achieved a high-power(0.5 W)Raman soliton(60 fs)at 4.3μm.These results,for the first time,to our knowledge,demonstrate that tapered fluorotellurite fibers can be used for high-power femtosecond pulse generation beyond4μm and high-power SC generation beyond 5μm,establishing them as an exceptional nonlinear medium for the development of high-power MIR fiber lasers in the 4–5μm spectral region.展开更多
基金National Natural Science Foundation of China(62005004,61675009)Natural Science Foundation of Beijing Municipality(4204091,KZ201910005006)China Postdoctoral Science Foundation(212423)。
文摘Ultra-broadband supercontinuum(SC)lasers covering the mid-infrared(MIR)region have significant applications in trace substance detection,national defense,and biomedical fields.Currently,high-power SC spanning2–5μm is still dominated by traditional fluoride(InF_(3))fibers.Although tellurite fibers,with their excellent chemical and thermal stability,have demonstrated significantly higher power scalability compared to other MIR fibers,their spectral broadening capabilities in the 4–5μm region remain largely unexplored.Here,we demonstrate a>10 W ultra-broadband flat SC spanning the 1.8–5.1μm spectral range in a fluorotellurite fiber using a cascaded soliton self-frequency shifting technique.The fluorotellurite fiber is precisely tapered to reconstruct dispersion and nonlinearity,which facilitates the evolution of the pre-stage Raman soliton into higherorder solitons,thereby enabling a new round of“rapid relay fission.”At a low pump power of 7.5 W,we also achieved a high-power(0.5 W)Raman soliton(60 fs)at 4.3μm.These results,for the first time,to our knowledge,demonstrate that tapered fluorotellurite fibers can be used for high-power femtosecond pulse generation beyond4μm and high-power SC generation beyond 5μm,establishing them as an exceptional nonlinear medium for the development of high-power MIR fiber lasers in the 4–5μm spectral region.
