强场中真空正负电子对产生的低密度近似  

Low density approximation of electron-positron pair production in strong field

作　　者：李烈娟 麦丽开·麦提斯迪克 王莉 谢柏松[1,2] LI Liejuan;Melike MOHAMEDSEDIK;WANG Li;XIE Baisong(College of Nuclear Science and Technology,Beijing Normal University,100875,Beijing,China;Institute of Radiation Technology,Beijing Academy of Science and Technology,100875,Beijing,China)

机构地区：[1]北京师范大学核科学与技术学院,北京100875 [2]北京市科学技术研究院辐射技术研究所,北京100875

出　　处：《北京师范大学学报（自然科学版）》2022年第5期743-747,共5页Journal of Beijing Normal University(Natural Science)

基　　金：国家自然科学基金资助项目(11875007)。

摘　　要：在空间均匀含时的强外场下真空正负电子对产生的研究中,从散射势转变点的角度,严格证明了源于量子Vlasov方程的低密度近似方法(low density approximation,LDA)与半经典的WKB(Wentzel-Kramers-Brillouin)方法等价.通过对典型例子进行数值计算和说明,对这2种方法的等价性进行了检验.当有较多转变点时,WKB积分变得烦琐,相较而言,LDA更具有计算优势.本研究将量子动力学过程和量子隧穿过程联系起来,有助于深入理解强场下真空中正负电子对的产生过程.Electron-positron pair production in time-dependent homogenous strong external electric field is investigated.For turning points of scattering potential,low-density approximation(LDA)arising from quantum Vlasov equation is proven to be equivalent to semi-classical WKB(Wentzel-Kramers-Brillouin)method.Typical examples are used to confirmed numerically the equivalency of these two methods.When there are too many turning points,WKB integrals become tedious,then LDA is a more convenient calculation technique.Our work by the combination of quantum kinetic process with quantum tunneling process will facilitate understanding of electronpositron pair production in the vacuum under strong fields.

关 键 词：强场物理 正负电子对产生 低密度近似 

分 类 号：O413[理学—理论物理]