Does the oscillatory behavior of the Momentum Spectrum depend on the basis in the Post-Transient Stage? (2410.16321v2)

Abstract: Pair creation by a spatially homogeneous, time-dependent electric field is studied within the framework of scalar quantum electrodynamics. We employ the standard Bogoliubov transformation approach to compute the single-particle distribution function in an adiabatic basis. We analyzed the distribution function of created particles in two different adiabatic bases (related by a unitary transformation). A novel dynamical scaling is observed while analyzing the oscillatory momentum spectrum of the pairs created by the Sauter pulsed field at intermediate times, calculated using the two adiabatic bases. In these bases, the same oscillatory momentum spectra are observed but at different times. However, when we scale the time by the point marking the end of the transient stage of dynamical evolution for each case of central momentum, the respective momentum spectra overlap. Furthermore, we study the time evolution of the momentum spectrum in the multi-photon regime and find that the spectra show a multi-modal profile structure at finite times for both choices of basis.