Numerical investigation on Coulomb impact on bouquetlike photoelectron momentum distributions

Deploying the strong-field approximation and the saddle point methods, we numerically simulate the Coulomb impact on the bouquetlike photoelectron momentum distributions (PMDs) induced by intense laser ionization of hydrogen atom. The bouquet-like PMDs, also dubbed as electron carpet-like PMDs, are interference structures perpendicular to laser polarization in PMDs. The results show that the bouquetlike interference PMDs are mostly altered for small momenta, for both the above-threshold ionization (ATI) and intra-cycle interference (ICI) fringes, compared with the Coulomb-free situation. We propose a correlation parameter (CP) to quantitatively elucidate the PMDs alterations due to Coulomb effect. Also, we formulate an expression for successfully tracing out the ATI and ICI fringes, which proves that the bouquetlike PMDs alterations are attributed to an extra action phase due to Coulomb interaction.