Low pump power coherent supercontinuum generation in heavy metal oxide solid-core photonic crystal fibers infiltrated with carbon tetrachloride covering 930–2500 nm

Abstract

All-normal dispersion supercontinuum (ANDi SC) generation in a lead-bismuth-gallate glass solid-core photonic crystal fiber (PCF) with cladding air-holes infiltrated with carbon tetrachloride (CCl4) is experimentally investigated and numerically verified. The liquid infiltration results in additional degrees of freedom that are complimentary to conventional dispersion engineering techniques and that allow the design of soft-glass ANDi fibers with an exceptionally flat near-zero dispersion profile. The unique combination of high nonlinearity and low normal dispersion enables the generation of a coherent, low-noise SC covering 0.93–2.5 µm requiring only 12.5 kW of pump peak power delivered by a standard ultrafast erbium-fiber laser with 100 MHz pulse repetition rate (PRR). This is a much lower peak power level than has been previously required for the generation of ANDi SC with bandwidths exceeding one octave in silica- or soft-glass fibers. Our results show that liquid-composite fibers are a promising pathway for scaling the PRR of ANDi SC sources by making the concept accessible to pump lasers with hundreds of megahertz of gigahertz PRR that have limited peak power per pulse but are often required in applications such as high-speed nonlinear imaging, optical communications, or frequency metrology. Furthermore, due to the overlap of the SC with the major gain bands of many rare-earth fiber amplifiers, our source could serve as a coherent seed for low-noise ultrafast lasers operating in the short-wave infrared spectral region.

Liquid‐Core Optical Fibers—A Dynamic Platform for Nonlinear Photonics

“…[119] The absolute dispersion values varied between -150 and -5 ps/nm/km for the 1-2 μm spectral range. In a few other experiments, Hoang, Van Le et al also presented several HCF designs infiltrated with CCl 4 showing flat normal dispersion in a broad spectral range (i.e., 0.8-1.7 μm [120] and all-normal up to 2.5 μm [121] ).…”

“…In a few other experiments, Hoang, Van Le et al. also presented several HCF designs infiltrated with CCl 4 showing flat normal dispersion in a broad spectral range (i.e., 0.8–1.7 $$\umu$$m [ 120 ] and all‐normal up to 2.5 $$\umu$$m [ 121 ] ).…”

“…have demonstrated efficient broadband self‐phase modulation in a widely normal and all‐normal dispersion domain, respectively (i.e., from 0.93–2.5 $$\umu$$W at sub‐nJ pulse energies). [ 120,121,162 ]…”

Numerical simulation of coherent mid-infrared supercontinuum generation based on carbon chloride core tapered photonic crystal fibers

“…Junaid et al filled the microstructure fiber with CS 2 and used 30 fs and 90 fs pulse pumps respectively to obtain a SC spectrum of 1-2.2 µm experimentally [28]. Le et al reported the discovery of high-quality, high-coherence SC covering 0.9-2.5 µm in lead-bismuth-gallate (PBG) glass PCF infiltrated with CCl 4 [29]. Alternatively, using tapered fibers is another method to enhance spectral broadening to the MIR region owing to their enhanced dispersion or nonlinearity design freedom [30].…”

High coherent supercontinuum generation in nitrobenzene liquid-core photonic crystal fiber with elliptical air-hole inner ring

“…High nonlinear PCF is an excellent nonlinear optical medium to generate supercontinuum [17] . In recent years, SCG in liquid-core bers has attracted more and more attention due to the superior performance of some inorganic solvents [18,19] , such as carbon disul de (CS 2 ) [20] , carbon tetrachloride (CCl 4 ) [21] , tetrachloroethylene (C 2 Cl 4 ) [22] , toluene [23] , nitrobenzene [24] and so on. These inorganic solvents have good transmission properties and large nonlinear coe cients in the visible to near-infrared spectral region, and also exhibit strong non-instantaneous nonlinearity due to the slow molecular motion of liquid [25] , which is one of the ideal nonlinear mediums for SCG [26] .…”