Dispersion tuning of nonlinear optical pulse dynamics in gas-filled hollow capillary fibers

We experimentally investigate the nonlinear dynamics of ultrashort laser pulses propagating in gas-filled hollow capillary fibres different dispersion regimes, which are achieved by tuning gas pressure. When pulse propagates anomalous regime we observe soliton accompanied with soliton-plasma effects, such as self-compression, resonant dispersive-wave emission fundamental well higher-order modes, blue-shifting and ionisation-induced splitting. Propagation vicinity zero-dispersion wavelength results splitting subsequent cross-phase modulation leading to generation an additional frequency-shifted band a 3-octave broad supercontinuum. In case normal flat this regime, experimental less described simulations that consider only propagation inside fibre. Free-space beam bulk gas, before entrance, suggest discrepancy is caused self-focusing ionisation altering spatial temporal shape, affecting both coupling efficiency capillary.