Vimal Mekha, Natile Michele, Lupi Jean-François, Guichard Florent, Descamps Dominique, Hanna Marc, Georges Patrick
Opt Lett. 2024 Jan 1;49(1):117-120. doi: 10.1364/OL.506009.
We demonstrate nonlinear temporal compression of a vortex beam by propagation in a gas-filled capillary. Starting from an ytterbium-based laser delivering 700 μJ 640 fs pulses at a 100 kHz repetition rate, the vortex beam is generated using a spiral phase plate and coupled to a capillary where it excites a set of four modes that have an overlap integral of 97% with a Laguerre-Gauss LG mode. Nonlinear propagation of this hybrid, orbital angular momentum (OAM)-carrying mode results in temporal compression down to 74 fs at the output. Beam and pulse characterizations are carried out to determine the spatial profile and temporal duration of compressed pulses. This result in multimode nonlinear optics paves the way towards the generation of OAM-carrying few-cycle pulses, isolated attosecond XUV pulses, and tunable UV pulses through resonant dispersive wave emission.
我们通过在充气毛细管中的传播展示了涡旋光束的非线性时间压缩。从一个基于镱的激光器开始，它以100 kHz的重复频率输出700 μJ、640 fs的脉冲，使用螺旋相位板产生涡旋光束，并耦合到毛细管中，在那里它激发一组与拉盖尔 - 高斯LG模式重叠积分达97%的四个模式。这种携带轨道角动量（OAM）的混合模式的非线性传播导致输出时时间压缩至74 fs。对光束和脉冲进行表征以确定压缩脉冲的空间分布和时间持续时间。多模非线性光学领域的这一结果为通过共振色散波发射产生携带OAM的少周期脉冲、孤立阿秒极紫外脉冲和可调谐紫外脉冲铺平了道路。
