Effects of pulse profile on electron-positron pair creation

We study the effects of the pulse profiles on electron-positron pair creation. Three localized time-dependent pulses, i.e., Sauter pulse, Gaussian pulse and cosine pulse, are studied through several proposals. The non-monochromatic pulse (Sauter or Gaussian pulse) creates more pairs than the monochromatic pulse (cosine pulse). To investigate the creation process, the relationship between the maximum pair number and the final pair number (which is called retracement) is analysed. The results show that the Gaussian pulse gives the smallest re-annihilation rate because the annihilation mostly happen in the high-energy region where less pairs are created, while the low-energy pairs mostly annihilate in the cosine case. The optimal pulse profiles, which maximize the total pair creation number, are found in three cases. Furthermore, an additional static field enhances the pair creation for all pusles. The optimal field parameters of the combination fields are calculated out. Copyright (C) EPLA, 2019