Abstract

Coherent scattering of radiation in periodic dielectric structures results in an electromagnetic dispersion relation which exhibits novel features such as new propagation modes and photonic band gaps. The latter topic has received much current attention for a variety of fundamental and practical reasons [1,2]. Furthermore, the theoretical calculation of the electromagnetic dispersion relation in such structures has become relatively sophisticated. However, experimental verification using traditional microwave techniques has been limited to determining the frequencies which define the gaps and to study localized defect modes. Here, we present the dispersion relation of a periodic dielectric array measured explicitly using the coherent microwave transient spectroscopy (COMITS) technique [3,4]. The experimental results are compared with theoretical predictions obtained using the plane-wave expansion technique [5].

© 1992 The Author(s)