AI 中文总结
该研究用级联全块状多通池压缩系统，从特定初始脉冲产生近单周期脉冲，实验与模拟验证其高效性，为强场等超快应用提供平台。
AI 中文摘要
我们通过实验演示了基于两个块状多通池的级联后压缩方案产生亚双周期光脉冲。从中心波长1030 nm、脉宽220 fs、能量100 μJ的脉冲出发，依次进行光谱展宽和脉冲压缩，首先将脉宽降至50 fs，最终在中心波长1058 nm处得到5.5 fs（1.6个光周期）的脉冲。超宽光谱由色散控制腔实现。全面的光谱、时间和空间表征证实了优异的脉冲质量。尽管第二个多通池的峰值功率是熔融石英自聚焦临界功率的数百倍，却未观察到明显的空间-光谱或空间-时间畸变，可将压缩后的40 μJ脉冲直接用于后续实验。非线性光谱展宽的数值模拟与实验结果高度吻合，验证了 underlying 物理图像。这些发现确立了块状多通池作为高效、紧凑、坚固的平台，用于产生具有优异光束质量的少周期脉冲，在强场和超快应用中展现出巨大潜力，包括极紫外产生和孤立阿秒脉冲生成。
英文摘要
We experimentally demonstrate the generation of sub-two-cycle optical pulses using a cascaded post-compression scheme based on two bulk multi-pass cells. Starting from 220 fs, 100 $μ$J pulses around 1030 nm, sequential spectral broadening and pulse compression reduce the pulse duration first to 50 fs and ultimately to 5.5 fs (1.6 optical cycles) at a central wavelength of 1058 nm. The ultra-broadband spectrum is enabled by a dispersion-controlled cavity. Comprehensive spectral, temporal, and spatial characterization confirms excellent pulse quality. Despite operating the second multi-pass cell at peak powers several hundred times above the critical power for self-focusing in fused silica, no significant spatio-spectral or spatio-temporal distortions are observed, enabling direct use of the compressed 40 $μ$J pulses in further experiments. Numerical simulations of the nonlinear spectral broadening show excellent agreement with the experimental results, supporting the underlying physical picture. These findings establish bulk multi-pass cells as an efficient, compact, and robust platform for generating few-cycle pulses with excellent beam quality, offering considerable potential for strong-field and ultrafast applications, including extreme-ultraviolet generation and isolated attosecond pulse production.
Comments11 pages, 6 figures
