We utilize the dispersion property of an X-ray filter material for the generation of a single sub-50-as pulse from high-order harmonics. The attosecond pulse, formed by selecting the spectral range of high-order harmonic radiation, contains an intrinsic chirp corresponding to the quadratic phase variation during a half cycle of a laser pulse. We show that this chirp can be compensated by using the negative group-delay dispersion of a thin X-ray filter, compressing the attosecond pulse down to sub-50-as.

Kim, K.T.Kim, C.M.Baik, M.G.Umesh, G.Nam, C.H.2026-02-05CompressioApplied Physics B: Lasers and Optics, 2004, 79, 5, pp. 563-5679462171https://doi.org/10.1007/s00340-004-1601-8https://idr.nitk.ac.in/handle/123456789/279372004Coherent lightComputational methodsDispersionsHarmonic generationIonizationLaser mode lockingMaterials sciencePhotonsAttosecond pulsesHarmonic radiationTime-dependent Schrödinger equations (TDSE)X-ray filtersFiber lasersWe utilize the dispersion property of an X-ray filter material for the generation of a single sub-50-as pulse from high-order harmonics. The attosecond pulse, formed by selecting the spectral range of high-order harmonic radiation, contains an intrinsic chirp corresponding to the quadratic phase variation during a half cycle of a laser pulse. We show that this chirp can be compensated by using the negative group-delay dispersion of a thin X-ray filter, compressing the attosecond pulse down to sub-50-as.