Planar prism spectrometer based on adiabatically connected waveguiding slabs
F. Civitci, M. Hammer, H.J.W.M. Hoekstra, Optics Communications 365 (2015) 29–37.

Oblique incidence of semi-guided waves on rectangular slab waveguide discontinuities: A vectorial QUEP solver
M. Hammer, Optics Communications 338 (2014) 447–456.