High-order harmonic generation by polyatomic molecules

25th Annual International Laser Physics Workshop

Odak, S.^1 ; Hasovi, E.^1 ; Miloevi, D.B.^1,2,3

Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, Sarajevo

71000, Bosnia and Herzegovina^1

Max-Born Institut, Max-Born Strasse 2a, Berlin

12489, Germany^2

Academy of Sciences and Arts of Bosnia and Herzegovina, Bistrik 7, Sarajevo

71000, Bosnia and Herzegovina^3

关键词: General expression;    Harmonic spectrum;    High order harmonic generation;    Linearly polarized laser field;    Particle systems;    Polyatomic molecules;    S-matrix theory;    Strong-field approximations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/826/1/012007/pdf
DOI  :  10.1088/1742-6596/826/1/012007

来源: IOP

【 摘 要 】

We present a theory of high-order harmonic generation by arbitrary polyatomic molecules based on the molecular strong-field approximation (MSFA) in the framework of the S-matrix theory. A polyatomic molecule is modeled by an (N + 1)-particle system, which consists of N heavy atomic (ionic) centers and an electron. We derived various versions (with or without the dressing of the initial and/or final molecular state) of the MSFA. The general expression for the T-matrix element takes a simple form for neutral polyatomic molecules. We show the existence of the interference minima in the harmonic spectrum and explain these minima as a multiple-slit type of interference. This is illustrated by numerical examples for the nitrous oxide (N2O) molecule exposed to strong linearly polarized laser field.