Analytical study of residual-current excitation during gas ionization by two-color laser pulse

23rd International Laser Physics Workshop

Silaev, A.A.^1 ; Kostin, V.A.^1 ; Laryushin, I.D.^1 ; Vvedenskii, N.V.^1

Institute of Applied Physics, Russian Academy of Sciences, University of Nizhny Novgorod, Nizhny Novgorod

603950, Russia^1

关键词: Analytical expressions;    Analytical investigations;    Analytical studies;    Fundamental frequencies;    Low frequency radiation;    Residual current;    Terahertz frequencies;    Two-color laser pulse;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/594/1/012020/pdf
DOI  :  10.1088/1742-6596/594/1/012020

来源: IOP

【 摘 要 】

This work is focused on the analytical investigation of the excitation of low-frequency residual current during gas ionization by two-color laser pulses. Such excitation is of great interest since it may be used to convert efficiently laser pulses into low-frequency radiation, in particular, into radiation of the terahertz frequency band. We derive analytical expressions for the residual current density for the cases when two-color laser pulse contains the main strong fundamental-frequency field and additional frequency-tunable field with the frequency close to the double or half frequency of the main field. Derived formulas are used to analyze and compare main features of residual-current excitation in the cases when additional field is second-or half-harmonic of the main field.