Large mode area waveguides with polarization functions by volume ultrafast laser photoinscription of fused silica

We present optical designs allowing large mode area light guiding by ultrafast laser photoinscription of bulk fused silica. If usual concepts are based on large core and depressed cladding, evanescently coupled multicore waveguides with coherent mode superposition can be effective solutions, where the introduction of nanostructured defects determines additional polarization functions.