Coherent Electron Wave Packet, CEWP, Interference in Attosecond Photoionization with Ultrashort Circularly Polarized XUV Laser Pulses

Abstract

Effects of coherent electron interference in attosecond photoionization with intense ultrashort circularly polarized extreme ultraviolet (XUV) laser pulses are studied. Simulations are performed on oriented one electron molecular ions H\(_2^+\) and H\(_3^{2+}\) by numerically solving appropriate time-dependent Schrödinger equations (TDSEs). It is found that due to interference of coherent continuum scattering electron wave packets, momentum stripes with intervals \(\varDelta p^s =2\pi /R\) are observed in angular distributions. The momentum stripes are independent of the laser polarization and wavelength, and these are always perpendicular to the molecular internuclear axis. Ionization with two color circularly polarized XUV laser pulses produces an asymmetry in angular distributions resulting from interference of coherent electron wave packets (CEWPs) from multiple pathway ionization. The multiple ionization pathway interference is shown to be sensitive to the pulse relative carrier envelope phase (CEP) and photoelectron kinetic energies. We describe these phenomena by a perturbation multi-photon ionization model, thus suggesting imaging and controlling methods for electrons in molecules on attosecond time scale.KeywordsElectron Wave PacketCircular PolarizationCarrier-envelope Phase (CEP)Electron InterferencePlane-polarized LaserThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.