Novel integrated photonics components are highly demanded to develop photonic integrated circuits, or sensing applications with lab-on-chip or lab-on-fiber approaches. Femtosecond laser inscription has demonstrated to be a very attractive approach being highly versatile as well as compatible with laser manufacturing technological transfer. In this framework, some of the innovations to come will result from optimized laser-based processing in prepared materials, namely in specialty glasses with a designed photosensitivity enhancement under laser irradiation.
In this framework, we recently demonstrated a new type of waveguides. Here, the positive refractive index modification, labelled type A, is sustained by the laser-induced photochemistry of silver-containing phosphate glasses, with a non-trivial distribution that corresponds to the creation of fluorescent silver clusters. Some of the inner features of the refractive index structures and associated waveguides show mesoscale dimensions of a few hundreds of nanometers, which is of interest for produce sub-wavelength modifications. In this paper, we will present recent results concerning the exploitation of such new waveguides, namely with the investigation of curvature losses and the creation of directional couplers. Additionally, periodically modulated waveguides are considered to address laser-fabricated waveguide Bragg grating functionality. Such development is in progress, especially targeting reflectivity in the visible range.