An optical waveguide includes a glass waveguide body and a waveguide core through which optical radiation propagates. The waveguide core includes: a body portion extending within the waveguide body, a coupling portion extending at the surface of the waveguide body, and an S-bent intermediate portion coupling the body portion and the coupling portion. An optical coupling arrangement (e.g., for coupling one or more optical fibers to a silicon photonics device) includes one such optical waveguide and a second optical waveguide including a respective waveguide body and one or more waveguide members. The second optical waveguide is coupled with the first optical waveguide with the waveguide member(s) facing the coupling portion of the first optical waveguide.