双振荡场空间分离对真空中电子-正电子对产生的影响  

Research on electron-positron pair production in vacuum induced by spatially separated dual oscillating fields

作　　者：赵文呈 江淼 徐妙华[1] 李英骏[1,2] ZHAO Wencheng;JIANG Miao;XU Miaohua;LI Yingjun(School of Science,China University of Mining and Technology Beijing,Beijing 100083,China;State Key Laboratory for Tunnel Engineering,China University of Mining and Technology Beijing,Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)理学院,北京100083 [2]中国矿业大学(北京),隧道工程灾变防控与智能建养全国重点实验室,北京100083

出　　处：《物理学报》2025年第5期51-60,共10页Acta Physica Sinica

基　　金：中国科学院先导项目(批准号:XDA25051000);国家自然科学基金(批准号:11974419,11605286,12204001)资助的课题.

摘　　要：当两个次临界振荡场在空间上发生交叠时,可以高效促进真空中正负电子对的产生.本研究旨在探究两场在交叠方向上的间距变化对电子对产生的影响.模拟结果显示,随着间距的增大,产率逐渐降低.通过对不同频率组合的比较,还发现空间分离时产率的变化快慢与频率组合密切相关.此外,在间距变化时,电子能谱结构的变化也表现出不同的特征.通过结合粒子跃迁能量分布概率对能谱图的结构进行了详细分析,发现高阶跃迁概率随距离增加的衰减速度大于低阶跃迁.此外,随着间距的增大,两个组合场共同作用的多光子效应逐渐减弱,而单个场通过多光子效应产生正负电子对的概率则逐渐增强.上述结果和规律均得到了很好的解释,它帮助我们更深入地理解空间局域化对电子对产生的影响,并对实验设计提供一定的指导.This work investigates the combination of two partially overlapping oscillating fields,aiming to analyze the effect of the separation distance between the fields on the production of electron-positron pairs in a vacuum.The process is simulated using computational quantum field theory(CQFT)method and the split-operator technique,which is based on the spacetime-dependent Dirac equation.The main focus is to analyze the influence of separation distance and frequency combination on the pairwise production rate and energy spectrum.The research results show that partially overlapping sub-critical oscillating fields can still effectively generate electron-positron pairs at small separation distances.The variation in separation distance along the overlapping direction significantly affects the pairwise production rate.For two oscillating fields with a fixed sum of frequencies,the separation distance has a notable effect on the pairwise production rate,with different frequency combinations exhibiting varying degrees of dependency.Further analysis of the energy spectrum reveals that the number and positions of spectral peaks are differently affected by the separation distance.Models with smaller frequency differences exhibit more concentrated energy distributions,generally presenting a single-peak structure.In contrast,models with larger frequency differences show more dispersed energy distributions,typically presenting a dual-peak structure.As the separation distance increases,the energy spectrum structure varies with different frequency combinations,especially for larger separation distances.In the case of larger frequency difference,the high-energy peak declines rapidly with separation distance increasing,leading to a lower proportion of high-energy electrons,while in the case of smaller frequency difference the change is relatively small.This phenomenon is further analyzed using energy transition probability distribution diagrams of particles.By analyzing the probability distribution diagrams of particle energy transiti

关 键 词：粒子对产生 多光子效应 计算量子场论 

分 类 号：O413.2[理学—理论物理]