研究目的
Investigating the control over the polarization and vortex charge of attosecond high-harmonic beams via simultaneous spin–orbit momentum conservation.
研究成果
The research demonstrates unprecedented control over the SAM, OAM, and divergence of EUV light fields through simultaneous spin–orbit angular momentum conservation in HHG. This opens new avenues for ultrafast studies of chiral systems and nanoscale optical manipulation.
研究不足
The study is limited by the computational time for simulations with thicker gas jets, the purity of the vortex modes generated, and the need for further quantitative measurements of harmonic ellipticity.
1：Experimental Design and Method Selection:
A bichromatic Mach–Zehnder interferometer is used to produce two collinear, vortex laser beams with opposite helicities derived from the fundamental and frequency-doubled output of an ultrafast Ti:sapphire amplifier. These beams are combined to yield a bicircular vortex beam that drives high-harmonic generation (HHG) in a supersonic expansion of Ar gas. The emitted harmonics are collected via an EUV spectrometer.
2：Sample Selection and Data Sources:
A supersonic expansion of Ar gas is used as the medium for HHG. The generated harmonics are analyzed using an EUV spectrometer and an EUV charge coupled device (CCD) camera.
3：List of Experimental Equipment and Materials:
Ti:sapphire amplifier, Mach–Zehnder interferometer, beta-barium borate crystal, achromatic waveplates, spiral phase plates (SPPs), dichroic mirror, delay stage, convex lenses, supersonic Ar gas jet, gold-coated cylindrical mirror, flat grating, EUV CCD array.
4：Experimental Procedures and Operational Workflow:
The setup involves generating LCP and RCP beams, applying topological charges via SPPs, combining beams to form a bicircular vortex, focusing into Ar gas for HHG, and analyzing the emitted harmonics.
5：Data Analysis Methods:
The spatial mode and spectrum of the SAM–OAM harmonics are analyzed using the EUV spectrometer and CCD. EUV magnetic circular dichroism (EUV MCD) measurements are used to quantify the helicity of the harmonics.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
