Directly recording diffraction phenomena in time domain

Abstract

By making use of a new technique for measuring the complete spatiotemporal electric field of light with micrometer spatial and femtosecond temporal resolution, we directly demonstrate the formation of the so-called boundary diffraction wave and Arago’s spot, as well as the superluminal propagation of a “diffraction-free” pulse. We believe that such spatiotemporally resolved measurements and the time-domain treatment of diffracting waves not only turn out to be useful for modern physical optics, especially in micro- and meso-optics, but also significantly aid in the understanding of diffraction phenomena in general.