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Full-Text Articles in Physics
Influence Of Gas Pressure On High-Order-Harmonic Generation Of Ar And Ne, Guoli Wang, Cheng Jin, Anh-Thu Le, C. D. Lin
Influence Of Gas Pressure On High-Order-Harmonic Generation Of Ar And Ne, Guoli Wang, Cheng Jin, Anh-Thu Le, C. D. Lin
Physics Faculty Research & Creative Works
We study the effect of gas pressure on the generation of high-order harmonics where harmonics due to individual atoms are calculated using the recently developed quantitative rescattering theory, and the propagation of the laser and harmonics in the medium is calculated by solving the Maxwell's wave equation. We illustrate that the simulated spectra are very sensitive to the laser focusing conditions at high laser intensity and high pressure since the fundamental laser field is severely reshaped during the propagation. By comparing the simulated results with several experiments we show that the pressure dependence can be qualitatively explained. The lack of …
Generation Of Isolated Attosecond Pulses In The Far Field By Spatial Filtering With An Intense Few-Cycle Mid-Infrared Laser, Cheng Jin, Anh-Thu Le, Carlos A. Trallero-Herrero, C. D. Lin
Generation Of Isolated Attosecond Pulses In The Far Field By Spatial Filtering With An Intense Few-Cycle Mid-Infrared Laser, Cheng Jin, Anh-Thu Le, Carlos A. Trallero-Herrero, C. D. Lin
Physics Faculty Research & Creative Works
We report theoretical calculations of high-order harmonic generation (HHG) of Xe with the inclusion of multielectron effects and macroscopic propagation of the fundamental and harmonic fields in an ionizing medium. By using the time-frequency analysis we show that the reshaping of the fundamental laser field is responsible for the continuum structure in the HHG spectra. We further suggest a method for obtaining an isolated attosecond pulse (IAP) by using a filter centered on axis to select the harmonics in the far field with different divergence. We also discuss the carrier-envelope-phase dependence of an IAP and the possibility to optimize the …
High-Order-Harmonic Generation Using Gas-Phase H₂O Molecules, Song-Feng Zhao, Cheng Jin, R. R. Lucchese, Anh-Thu Le, C. D. Lin
High-Order-Harmonic Generation Using Gas-Phase H₂O Molecules, Song-Feng Zhao, Cheng Jin, R. R. Lucchese, Anh-Thu Le, C. D. Lin
Physics Faculty Research & Creative Works
We investigate high-order-harmonic generation of isotropically distributed gas-phase H₂O molecules exposed to an intense laser field. The induced dipole of each individual molecule by the laser field is first calculated using the recently developed quantitative rescattering theory. In a thin medium, harmonic spectra generated coherently from all the molecules are then calculated by solving Maxwell's equation of propagation. By using accurate transition dipoles of H₂O, we show that the harmonics in the lower plateau region are quite different from models that employ the simpler strong-field approximation. We also examine the magnitude and phase of the harmonics and their dependence on …