Open AccessJoint Measurements of Terahertz Wave Generation and High-Harmonic Generation from Aligned Nitrogen Molecules Reveal Angle-Resolved Molecular Structures
Author(s) -
Yindong Huang,
Chao Meng,
Xiaowei Wang,
Zhihui Lü,
Dongwen Zhang,
Wenbo Chen,
Jianlin Zhao,
Jianmin Yuan,
Zengxiu Zhao
Publication year - 2015
Publication title -
physical review letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.688
H-Index - 673
eISSN - 1079-7114
pISSN - 0031-9007
DOI - 10.1103/physrevlett.115.123002
Subject(s) - terahertz radiation , high harmonic generation , photoionization , ionization , laser , atomic physics , materials science , molecule , second harmonic generation , harmonic , physics , molecular physics , optics , ion , quantum mechanics
We report the synchronized measurements of terahertz wave generation and high-harmonic generation from aligned nitrogen molecules in dual-color laser fields. Both yields are found to be alignment dependent, showing the importance of molecular structures in the generation processes. By calibrating the angular ionization rates with the terahertz yields, we present a new way of retrieving the angular differential photoionization cross section (PICS) from the harmonic signals which avoids specific model calculations or separate measurements of the alignment-dependent ionization rates. The measured PICS is found to be consistent with theoretical predications, although some discrepancies exist. This all-optical method provides a new alternative for investigating molecular structures.