Optical solitons in hollow-core fibres

HISOL: High-energy soliton dynamics enable ultrafast far-ultraviolet laser sources

“…85 However, antiresonant fibers offered a (supposedly) unique combination of significant anomalous dispersion and low-loss guidance across a huge bandwidth, and this allowed for many important soliton dynamics to be observed. 18 And indeed, at the core sizes of antiresonant fibers that guide far-UV light (typically 20-30 μm in diameter), the propagation loss of even an ideal capillary is so high that any infrared pulse launched into it virtually disappears before it ever has the chance to self-compress. Antiresonant fibers do not present this problem.…”

“…The temporal profile of the UV pulses was not measured directly, but comparison with accurate numerical simulations suggested a pulse duration below 2 fs, and other work had previously confirmed similar durations in antiresonant fibers generated through the same mechanism. 69,70 An alternative view of the origin of the HISOL concept, which is how the idea first came into being, 18,57 is as the consequence of scaling laws for soliton dynamics in gas-filled fibers. Starting with the original results in antiresonant fibers, observing similar dynamics in a larger core requires more energy, a longer fiber, and lower gas pressure, as shown in Fig.…”