中红外偏振态门驱动产生高效的极宽超连续谱

摘要

We theoretically investigate the process of the efficient ultra-broadband supercontinuum generation in the mid-infrared polarization gating. The polarization gating at 2000 nm is adopted to restrict the recombination of the electron into one-half optical cycle and extend the spectrum cut-off to 270 eV. And a 0. 5 fs ultraviolet pulse is synthesized to the polarization gating to control the ionization process. Then the harmonic intensity is enhanced by 4-5 orders, and a 240eV supercontinuum is obtained, supporting a 16 as pulse generation. By filtering out different ranges of the supercontinuum, isolated 110 as pulses with tunable central wavelengths are efficiently generated.%研究了在中红外偏振态门驱动下高效产生极宽超连续谱的过程.利用波长为2000 nm的偏振态门激光场可以将电子的同复控制在半个光周期内,并且将谐波谱的截止区拓展到270 eV.在偏振态门中加入0.5 fs的紫外控制脉冲,可以对谐波的电离过程进行控制,把谐波的强度提高了4-5个数量级,并得到了谱宽为240 eV的极宽超连续谱.该极宽超连续谱在傅里叶变换极限下支持脉宽仅为16 as的单个脉冲的产生.通过过滤超连续谱中不同次数的谐波,可以得到一系列波长可调的110 as的高强度单脉冲.