Terahertz emission during interaction of ultrashort laser pulses with gas cluster beam

International Conference of Young Scientists and Specialists "Optics-2015"

Balakin, A.V.^1 ; Borodin, A.V.^1,2 ; Dzhidzhoev, M.S.^1 ; Gorgienko, V.M.^1 ; Esaulkov, M.N.^2 ; Zhvaniya, I.A.^1 ; Kuzechkin, N.A.^2 ; Ozheredov, I.A.^1 ; Sidorov, A Yu^1 ; Solyankin, P.M.^1 ; Shkurinov, A.P.^1,2

Faculty of Physics and International Laser Center, M.V. Lomonosov Moscow State University, Moscow

119991, Russia^1

Institute on Laser and Information Technologies, Russian Academy of Sciences, Shatura

140700, Russia^2

关键词: Fundamental frequencies;    Intense femtosecond laser pulse;    Laser pulse duration;    Laser-cluster interaction;    Optical pulse energy;    Terahertz emissions;    Terahertz generation;    Two-color excitation;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/735/1/012021/pdf
DOI  :  10.1088/1742-6596/735/1/012021

来源: IOP

【 摘 要 】

We present the results of experimental study of terahertz (THz) generation in gas cluster beam excited by intense femtosecond laser pulses. Cluster beam was produced by partial condensation of pure Ar and mixtures CF2Cl2+He, Ar+He during their expansion through a conical nozzle into vacuum. There were used two excitation schemes in our experiments: single color and two color (fundamental frequency mixed with its second harmonic). We have studied how THz signal scales with various control parameters such as laser pulse duration, gas backing pressure and laser pulse energy. Simultaneously we measured intensity of X-Ray emission which originates from laser-cluster interaction. We found that in a single color scheme energy of THz pulses from Ar cluster beam strongly decreases in the region of minimum laser pulse duration while X-Ray power is maximal under these conditions. Both in single- and two color excitation regimes THz signal demonstrated growth without saturation with increasing of optical pulse energy up to its peak value of 25 mJ.