Exploration of Below-Threshold Harmonic Generation Mechanisms of Cesium Atoms in Intense Mid-Infrared Laser Pulses

  • Y.-J. ChenEmail author
  • C. Laughlin
  • S.-I. Chu
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 125)


We present a non-perturbative quantum study of high-order harmonic generation (HHG) of Cesium atoms in intense mid-infrared laser pulses. An accurate angular-momentum—dependent model potential is constructed for the high-precision description of the Cs atom electronic structure. The three-dimensional time-dependent Schrodinger equation is solved accurately and efficiently by means of the time-dependent generalized pseudospectral methods (TDGPS) [Tong and Chu, Chem Phys 217(2–3), 119–130 (1997)].Besides the expected odd harmonics, the calculated HHG power spectra show additional structures due to the strong 6s–np couplings. The spectral and temporal characteristics of the HHG are further explored through the wavelet transformation [Tong and Chu, Phys Rev A 6102(2), 21802 (2000)]. As a result, we can investigate the prevailing mechanisms in different energy regimes, especially those contributing to the below- and near-threshold harmonics [Power et al., Nat Photon 4(6), 352–356 (2010); Soifer et al., Phys. Rev. Lett. 105(14), 143904 (2010); Yost et al., Nat Phys 5(11), 815–820 (2009)].


Time Profile Wavelet Transformation Group Delay Energy Regime Cesium Atom 
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This work was partially supported by the U.S. Department of Energy and by the U.S. National Science Foundation. We also would like to acknowledge the partial support of National Science Council of Taiwan (Grant No. 100-2119-M-002-013-MY3) and National Taiwan University (Grant No. 10R80700).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Department of Physics, Center for Quantum Science and EngineeringNational Taiwan UniversityTaipeiTaiwan
  2. 2.School of Mathematical SciencesUniversity of NottinghamNottinghamUK
  3. 3.Department of ChemistryUniversity of KansasLawrenceUSA

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