Deep-UV to Mid-IR Supercontinuum Generation driven by Mid-IR Ultrashort Pulses in a Gas-filled Hollow-core Fiber

Abstract

Supercontinuum (SC) generation based on ultrashort pulse compression constitutes one of the most promising technologies towards ultra-wide bandwidth, high-brightness, and spatially coherent light sources for applications such as spectroscopy and microscopy. Here, multi-octave SC generation in a gas-filled hollow-core antiresonant fiber (HC-ARF) is reported spanning from 200 nm in the deep ultraviolet (DUV) to 4000 nm in the mid-infrared (mid-IR) having an output energy of 5 μJ. This was obtained by pumping at the center wavelength of the first anti-resonant transmission window (2460 nm) with ~100 fs pulses and an injected pulse energy of ~8 μJ. The mechanism behind the extreme spectral broadening relies upon intense soliton-plasma nonlinear dynamics which leads to efficient soliton self-compression and phase-matched dispersive wave (DW) emission in the DUV region. The strongest DW is observed at 275 nm which corresponds to the calculated phase-matching wavelength of the pump. Furthermore, the effect of changing the pump pulse energy and gas pressure on the nonlinear dynamics and their direct impact on SC generation was investigated. This work represents another step towards gas-filled fiber-based coherent sources, which is set to have a major impact on applications spanning from DUV to mid-IR.

Single-mode, low loss hollow-core anti-resonant fiber designs

“…A unique and striking feature of hollow-core fiber is that most of the light (>99.99%) can be guided in the central air-core with only a tiny fraction of light overlapping with the surrounding glass structure, hence increasing the optical damage threshold and reducing material absorption significantly [4][5][6]10,11]. These fibers have found numerous applications including high power delivery [12], ultra-short pulse delivery [13], pulse compression [14], mid-infrared (mid-IR) transmission [15], terahertz guidance [16], and gas-based nonlinear optics [17][18][19][20][21][22][23][24][25]. In general, based on the guidance mechanism, there are two types of hollow-core fibers which have been proposed.…”

Supercontinuum generation from deep-UV to mid-IR in a noble gas-filled fiber pumped with ultrashort mid-IR pulses

“…The most efficient DW was located at ~275 nm with an estimated energy of 1.42 μJ (corresponding to 28.4 % of the total output power). The nonlinear mechanism behind the observed multi-octave spectral broadening relies upon strong soliton-plasma interaction and it has been extensively described in literature [1][2][3][7][8][9].…”

Glass: The carrier of light—Part II—A brief look into the future of optical fiber

“…[61][62][63] A second example is gas-filled silica-based hollow core fibers tailored to permit nonlinear IR (to >4 µm) light generation. 64,65 These are useful examples where silica takes a bite out of the spectral range and application space traditionally reserved for heavy metal oxide and nonoxide, specifically chalcogenide, glass fibers.…”