Open AccessGeneration of necklace-shaped high harmonics in a two-color vortex field
Author(s) -
Ju-Kui Xue,
Candong Liu,
C. T. Zhou,
Shuangchen Ruan
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.427595
Subject(s) - harmonics , physics , optics , vortex , high harmonic generation , optical vortex , necklace , field (mathematics) , angular momentum , adiabatic process , laser , classical mechanics , quantum mechanics , mechanics , mathematics , voltage , combinatorics , pure mathematics
We numerically studied gas high-harmonic generation in a two-color vortex laser field using the non-adiabatic Lewenstein model. Macroscopic responses were calculated by numerically solving the three-dimensional propagation equation in cylindrical coordinates. It was confirmed that unique high-harmonic signals with necklace-like shapes exhibit orbital angular momentum (OAM). The azimuthally distributed necklace harmonics exhibit periodic modulation as a function of laser frequency and topological charges of the driving field. Phase investigation showed that the OAM of the necklace harmonics is attributable to the tuning of the relative intensity of the two driving pulses. These findings provide a new dimension for high-harmonic manipulation in the vortex field. The two-color vortex field is the first scheme proposed for manipulating the intensity profile of high harmonics.