Phase-matched harmonic generation in gas-filled waveguides in the vicinity of a multiphoton resonance

Femtosecond laser micromachining of integrated glass devices for high‐order harmonic generation

“…Nowadays, the generation of XUV radiation by HHG is at the base of advanced spectroscopic techniques for probing ultrafast electron dynamics in atomic and molecular physics, and for the generation of attosecond pulses in time‐resolved pump‐probe measurements 14–16 . Since its demonstration, 17 the application of capillaries to HHG and attosecond pulse generation has attracted great interest 13,18,19 . If compared to more traditional generation approaches, based on gas‐jets produced by pulsed valves, capillaries allow achieving both laser beam and gas confinement for a longer interaction length, thus leading to a dramatic increase of the generation yield.…”

“…[14][15][16] Since its demonstration, 17 the application of capillaries to HHG and attosecond pulse generation has attracted great interest. 13,18,19 If compared to more traditional generation approaches, based on gas-jets produced by pulsed valves, capillaries allow achieving both laser beam and gas confinement for a longer interaction length, thus leading to a dramatic increase of the generation yield. Moreover, capillaries can be filled with gas both in static and continuous-flow regimes, meaning that they are not subdued to technological limitations on repetition rate as pulsed valves and can be applied to high-repetitionrate lasers.…”

Analytical treatment of quasi-phase matching of high-order harmonics in multijet laser plasmas: influence of free electrons between jets, intrinsic phase, and Gouy phase

“…The characteristic feature of laser plasmas for HHG is the presence of a significant amount of free electrons compared to noble gases. Previously, phase mismatch compensation was obtained by using counter-propagating driving beams [4,5], off-axial phase matching [6], phase matching in low-frequency fields [7], control of the pressure in modulated waveguides [8], the addition of a buffer gas with anomalous dispersion [9] and self-focusing by the Kerr nonlinearity [10]. One should note that gases used in HHG phase matching experiments are usually much denser than laser plasma.…”

Утроение Частоты Сверхкороткого Лазерного Импульса В Аргоне

“…В предлагаемой работе численным методом изучен процесс ГТГ, возбуждаемой интенсивным сверхкоротким лазерным импульсом длительностью 5 фс (нами такая задача ставится впервые), с учетом влияния ионизации газа и дисперсии высоких порядков на эффективность ГТГ. Поскольку взаимодействие лазерного излучения с исследуемым газом во многих экспериментах реализовано [13][14][15] внутри волоконных трубок, то влиянием эффектов дифракции можно пренебречь. Таким образом, теоретический подход работы приближен к реальной экспериментальной ситуации ГТГ в аргоне.…”