The Singular Optics of Random Light: a 2D vectorial investigation

In this thesis, we explore the physics of optical singularities. We investigate them in light waves propagating randomly in a planar nanophotonic chip. With a custom-built nearfield microscope, we map the electromagnetic field resulting from the interference of these light waves. Our technique gives access to the full vectorial and complex nature of such an electromagnetic field, with subwavelength resolution. The resulting information allows us to precisely pinpoint and characterize the multitude of singularities that arise in the random light field. We detect phase singularities in the Cartesian components of light’s vector field, i.e., points where the phase of the field components is undetermined and it circulates in a vortical flow around them (Part II).Moreover, we identify polarization singularities, e.g., C points: locations where the vector of light’s electric field describes a perfect circle in time (Part III)..