Vectorial optical field reconstruction by attosecond spatial interferometry

Abstract

An electrical pulse E(t) is defined completely by its time-dependent amplitude and polarization direction. For opticalpulses the manipulation and characterization of the light polarization state is fundamental because of its relevance inseveral scientific and technologicalfields. In this work, we demonstrate the complete temporal reconstruction of theelectricfield of few-cycle pulses with a complex time-dependent polarization. Our experimental approach is based onextreme ultraviolet interferometry with isolated attosecond pulses and on the demonstration that the motion of anattosecond electron wave packet is sensitive to perturbingfields only along the direction of its motion. By exploiting thesensitivity of interferometric techniques and by controlling the emission and acceleration direction of the wave packet,pulses with energies as low as a few hundreds of nanojoules can be reconstructed. Our approach reveals the possibility tocharacterize completely the electricfield of the pulses typically used in visible pump–probe spectroscopy