Abstract
We theoretically investigate the strong-field ionization of heteronuclear diatomic molecules, CO and NO, by calculating the photoelectron angular distribution and the photoelectron momentum distribution in circularly polarized fields. We find that the photoelectron angular distribution and the photoelectron momentum distribution of CO are inversion asymmetric, but symmetric about the molecular axis, most of the photoelectrons are ejected from the neighborhood of the C core. In contrast, for NO the photoelectron angular distribution and photoelectron momentum distribution are nearly fourfold symmetric about the molecular axis and its vertical axis, which means that the photoelectrons are equally ejected from the neighborhood of the N and O cores. By our results, the photoelectron angular distribution and photoelectron momentum distribution can be used to imprint the molecular orbitals.
Acknowledgments
The work was supported by the National Science Foundation of China under Grant No. 11104167, the Excellent Middle-Aged and Youth Scientist Award Foundation of Shandong Province of China (Grant No. BS2011SF021), General Financial Grantfrom the China Postdoctoral Science Foundation (Grant No. 2011M501120), and the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry.