【摘 要】
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The photoionization by two elliptically polarized, time delayed attosecond pulses is investigated to display a momentum distribution having the helical vortex or ring structures. The results are obtained by the strong field approximation method and analyz
【机 构】
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CollegeofPrecisionInstrumentandOptoelectronicsEngineering,TianjinUniversity,Tianjin300072,ChinaCivil
【出 处】
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ChineseOpticsLetters
论文部分内容阅读
The photoionization by two elliptically polarized, time delayed attosecond pulses is investigated to display a momentum distribution having the helical vortex or ring structures. The results are obtained by the strong field approximation method and analyzed by the pulse decomposition. The ellipticities and time delay of the two attosecond pulses are found to determine the rotational symmetry and the number of vortex arms. For observing these vortex patterns, the energy bandwidth and temporal duration of the attosecond pulses are ideal.
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