Asymmetric pulse effects on pair production in polarized electric fields

查看全文 作　　者：Obulkasim [1,2]Olugh;Zi-Liang [3]Li;Bai-Song [1,4]Xie 机构地区：[1]Key Laboratory of Beam Technology of the Ministry of Education,and College of Nuclear Science and Technology,Beijing Normal University,Beijing 100875,China;[2]Xinjiang Police College,Urumqi 830011,China;[3]School of Science,China University of Mining and Technology,Beijing 100083,China;[4]Beijing Radiation Center,Beijing 100875,China 出　　处：《High Power Laser Science and Engineering》索引2020年第8卷第4期,共11页 基　　金：supported by the National Natural Science Foundation of China(NSFC)under Grant Nos.11875007 and 11935008;supported by the NSFC under Grant No.11705278。 摘　　要：Using the Dirac–Heisenberg–Wigner formalism,effects of the asymmetric pulse shape on the generation of electronpositron pairs in three typical polarized fields,i.e.,linear,middle elliptical and circular fields,are investigated.Two kinds of asymmetries for the falling pulse length,short and elongated,are studied.We find that the interference effect disappears with the shorter pulse length and that the peak value of the momentum spectrum is concentrated in the center of the momentum space.In the case of the extending falling pulse length,a multiring structure without interference appears in the momentum spectrum.Research results show that the momentum spectrum is very sensitive to the asymmetry of the pulse as well as to the polarization of the fields.We also find that the number density of electronpositron pairs under different polarizations is sensitive to the asymmetry of the electric field.For the short falling pulse,the number density can be significantly enhanced by over two orders of magnitude.These results could be useful in planning high-power and/or high-intensity laser experiments. 关 键 词：asymmetric pulse electron-positron pair production polarized fields