利用扭转双脉冲驱动激光产生偏振方向可控的阿秒脉冲(特邀)  

Generation of Polarization-direction-controllable Attosecond Pulses with Twisting Double Laser Pulses(Invited)

作　　者：杨立岗 杜进旭 王国利[1] YANG Ligang;DU Jinxu;WANG Guoli(College of Physics and Electronic Engineering,Northwest Normal University,Lanzhou 730070,China)

机构地区：[1]西北师范大学物理与电子工程学院,兰州730070

出　　处：《光子学报》2024年第6期83-91,共9页Acta Photonica Sinica

基　　金：国家自然科学基金(No.12364040)。

摘　　要：研究了扭转双脉冲激光参数对产生高次谐波和阿秒脉冲偏振方向的影响。结果表明,当两束同频线偏振激光脉冲偏振方向正交并具有合适的时间延迟(或相位差)时,改变它们之间的强度比,可以在垂直于激光传播方向的平面内得到任意偏振方向的线极化阿秒脉冲,而激光载波包络相位不会对这种调控产生显著影响。此外,在合适的激光强度比下,利用两束激光脉冲之间的偏振夹角也可以有效控制阿秒脉冲的偏振方向。为产生偏振方向可控阿秒脉冲提供了一种简单易操作的方案。Strong field physics has evolved throughout the decades,and numerous unprecedented physical phenomena have been observed.High order harmonics generation,as an essential phenomenon in strong-field physics,has resulted in significant improvements in related research and applications since their first experimental discovery in 1987.After the first experimental observation of attosecond bursts from gas harmonic generation in 2001,a variety of gating techniques were used to obtain shorter and shorter isolated attosecond pulses,and attosecond pulses provide an important tool for observing ultrafast electron dynamics in matter on the atom's time scale.In addition to the intensity and width of the attosecond pulses,the research also focuses on the modulation of their polarization state.Because polarization-state controllable attosecond pulses can provide more degrees of freedom for manipulating ultrafast processes,they have important applications in chiral identification,magnetic circular dichroism,and spin currents.Two-colorω+2ωlaser is a very common type of driving field used in the harmonic and attosecond pulse generation.The intensity of harmonics can be improved and the harmonic cut-off can be extended effectively by using linear polarization two laser pulses with parallel polarization direction.The elliptically polarized attosecond pulse can be generated by using two pulses with orthogonal polarization or with a certain angle.In recent years,homochromatic dual laser pulses(ω+ω)have attracted attention in the study of molecules and atoms in the strong laser fields.The two laser beams are obtained by splitting a linearly polarised laser beam into two by means of a commonly used interferometer or waveplate.The time delay,phase delay,intensity ratio and the polarization angle between two beams can be easily modulated by additional optical elements such as waveplates and irises.When two laser pulses are polarized in parallel directions,the central frequency of the synthesized laser electric field changes with time d

关 键 词：双脉冲激光场 高次谐波 阿秒脉冲 偏振方向 调控 

分 类 号：O562.4[理学—原子与分子物理]