Soliton-Plasma Interactions and Dispersive-Wave Emission Beyond Two-Photon Resonances in Gas-Filled Hollow Capillary Fibres

Recently we have demonstrated soliton effects at high energy (0.3 mJ) in helium- and neon-filled hollow capillary fibres (HCF) [1]. We observed pulse self-compression to single-cycle durations and the generation of deep (DUV) and vacuum ultraviolet (VUV) radiation at record energy levels for a tunable source. Here, we demonstrate that soliton dynamics in capillary fibres can also be accessed with argon- and krypton-filled HCF, although ionisation effects then start to play a larger role. We also find that the DUV and VUV generation through resonant dispersive-wave (RDW) emission can be achieved at wavelengths considerably shorter than the two-photon resonances in each gas—something surprising, given previous work in gas-filled photonic crystal fibres HC-PCF [2], where soliton-related effects have been previously extensively explored at pJ pulse energy levels [3].