Electron–positron pair creation by counterpropagating laser pulses: role of carrier envelope phase

Abstract

Abstract: The effect of carrier envelope phase (CEP) on the spatio-temporal distribution of electron–positron pairs created by ultra-intense counterpropagating femtosecond laser pulses is studied. When the laser pulses are linearly polarized, the temporal distribution of the pairs is found to be sensitive with CEP. Same analysis is also done for the counterpropagating circularly e-polarized laser pulses. It is seen that when the counterpropagating laser pulses are both right (left) circularly polarized, the effect of the CEP is insignificant. On the other hand when the superimposed fields are in the combination of right and left circular polarizations, the CEP dependence comes in the invariant electric and magnetic fields structure and hence it reflects in the particle–antiparticle temporal distribution. However, the average number of total pairs is not greatly influenced by CEP for both the polarizations. Graphical abstract: [Figure not available: see fulltext.].