Woodbury D, Feder L, Shumakova V, Gollner C, Schwartz R, Miao B, Salehi F, Korolov A, Pugžlys A, Baltuška A, Milchberg H M
Opt Lett. 2018 Mar 1;43(5):1131-1134. doi: 10.1364/OL.43.001131.
We report on, to the best of our knowledge, the first results of laser plasma wakefield acceleration driven by ultrashort mid-infrared (IR) laser pulses (λ=3.9 μm, 100 fs, 0.25 TW), which enable near- and above-critical density interactions with moderate-density gas jets. Relativistic electron acceleration up to ∼12 MeV occurs when the jet width exceeds the threshold scale length for relativistic self-focusing. We present scaling trends in the accelerated beam profiles, charge, and spectra, which are supported by particle-in-cell simulations and time-resolved images of the interaction. For similarly scaled conditions, we observe significant increases in the accelerated charge, compared to previous experiments with near-infrared (λ=800 nm) pulses.
据我们所知，我们首次报告了由超短中红外（IR）激光脉冲（λ = 3.9μm，100飞秒，0.25太瓦）驱动的激光等离子体尾场加速的结果，该脉冲能够与中等密度气体射流进行近临界和超临界密度相互作用。当射流宽度超过相对论自聚焦的阈值尺度长度时，会发生高达约12 MeV的相对论电子加速。我们展示了加速束轮廓、电荷和光谱的标度趋势，这些趋势得到了粒子模拟和相互作用的时间分辨图像的支持。在类似的标度条件下，与之前使用近红外（λ = 800 nm）脉冲的实验相比，我们观察到加速电荷有显著增加。
