标题： 使用共振增强的高阶谐波产生阿秒脉冲 显示英文标题

标题： Attosecond pulse production using resonantly-enhanced high-order harmonics

摘要： 我们从理论上研究氙气中的巨共振对连续高阶共振增强谐波之间相位差的影响，并计算由这些谐波产生的阿托秒脉冲的持续时间。 在某些条件下，共振引起的去相位补偿了非共振谐波固有的相位差。 我们通过分析方法找到这些条件，并将其与数值结果进行比较。 这种谐波同步与共振引起的强度增加相结合，可以使阿托秒脉冲缩短一个数量级以上；后者增强放松了阿托秒脉冲产生所需的紫外过滤要求。 使用双色驱动场可以进一步增加强度。 特别是，谐波谱中的类似焦点特征导致生成效率提高两个数量级，但伴随着极端紫外脉冲的延长。 显示英文摘要

摘要： We study theoretically the effect of the giant resonance in Xe on the phase difference between the consecutive high order resonantly-enhanced harmonics and calculate the duration of the attosecond pulses produced by these harmonics. For certain conditions resonantly-induced dephasing compensates the phase difference which is intrinsic for the off-resonance harmonics. We find these conditions analytically and compare them with the numerical results. This harmonic synchronization allows attosecond pulse shortening in conjunction with the resonance-induced intensity increase by more than an order of magnitude; the latter enhancement relaxes the requirements for the UV filtering needed for the attosecond pulse production. Using a two-color driving field allows further increase of the intensity. In particular, a caustic-like feature in the harmonic spectrum leads to the generation efficiency growth up to two orders of magnitude, however accompanied by an elongation of the XUV pulse.