Macroscopic effect of plasmon-driven high-order-harmonic generation

作者:Wang, Feng; Liu, Weiwei; He, Lixin; Li, Liang; Wang, Baoning; Zhu, Xiaosong; Lan, Pengfei*; Lu, Peixiang*
来源:Physical Review A, 2017, 96(3): 033407.
DOI:10.1103/PhysRevA.96.033407

摘要

We present a numerical method to calculate the macroscopic harmonic spectrum generated from the gasexposed nanostructure. This method includes the propagation of plasmonic and harmonic fields in the macroscopic medium as well as the response of the single atom exposed to plasmonic field. Based on the simulation, we demonstrate that the macroscopic harmonic yields drop dramatically in the high-energy region. This result well interprets the disagreement in the cutoff between the single-atom prediction and the experimental detection. Moreover, we also show that the harmonic cutoff difference induced by a pi shift in carrier-envelope phase (CEP) of laser pulses depends sensitively on the spatial position. However, when the collective effect of plasmon-driven high-order-harmonic generation is considered, this cutoff difference is eliminated.