- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Semi-integer harmonic generation from an argon atom by bichromatic counter-rotating circularly polarized laser field
摘要： We theoretically investigated the properties of the high-order harmonic generation from an argon atom by bichromatic counter-rotating circularly polarized (BCCP) laser field. The harmonic spectra are gradually splitting and the harmonic orders move towards the higher frequency. Meanwhile, the integer and semi-integer harmonic emission will be generated when the frequency ratios of right- and left-circularly polarized laser are semi-integer. The emission mechanism of the semi-integer-order harmonics have been investigated by using the rules of photon absorption and emission.
关键词： bichromatic counter-rotating circularly polarized laser field,photon absorption and emission,high-order harmonic generation,semi-integer-order
更新于2025-09-23 15:21:01
-
Absorption and opacity threshold for a thin foil in a strong circularly polarized laser field
摘要： We show that a commonly accepted transparency threshold for a thin foil in a strong circularly polarized normally incident laser pulse needs a refinement. We present an analytical model that correctly accounts for laser absorption. The refined threshold is determined not solely by the laser amplitude, but by other parameters that are equally or even more important. Our predictions are in perfect agreement with particle-in-cell simulations. The refined criterion is crucial for configuring laser plasma experiments in the high-field domain. In addition, an opaque foil steepens the pulse front, which can be important for numerous applications.
关键词： particle-in-cell simulations,transparency threshold,circularly polarized laser field,laser absorption,thin foil
更新于2025-09-19 17:13:59
-
irradiated by a co-rotating two-color circularly polarized laser field
摘要： The high-order harmonic generation process of H2+ in a co-rotating two-color circularly polarized laser pulse was investigated by numerically solving the time-dependent Schr?dinger equation. Compared with the target of the atom, the harmonic intensity of H2+ is remarkably enhanced. Moreover, the harmonic intensity of H2+ approaches its maximum when the electric field amplitude ratio of the fundamental frequency and the second one is approximately 1:2.3. By analyzing the evolution of the time-dependent wave packets, the enhancement of harmonic intensity may be attributed to an increase in the probability of the ionized electron recolliding with the parent ion. In addition, the dependence of harmonic intensity on the internuclear distance and the alignment angle of H2+ is explored. We found that the ellipticity of the particular harmonic order changes with the molecular alignment angle, which provides a chance to generate an extreme ultraviolet coherent light pulse with controllable polarization.
关键词： time-dependent Schr?dinger equation,H2+,harmonic intensity,alignment angle,extreme ultraviolet coherent light pulse,controllable polarization,co-rotating two-color circularly polarized laser field,internuclear distance,high-order harmonic generation
更新于2025-09-12 10:27:22