Abstract
Dielectric reflectors have recently been proposed to be a key component for future wireless terahertz communication systems. Here, we investigate the dispersion properties of a mirror which consists of nine layers of two different dielectric materials. The layers differ considerably in their refractive index. The structure is highly reflecting and omnidirectional in a very broad frequency band. We find that the group delay is in the order of picoseconds inside the frequency band of interest (330-370 GHz), which is an acceptable value for such a component.