Investigation of the optical properties of a spherical distributed Bragg reflector

Abstract

The dependence of the optical properties of a spherical distributed Bragg reflector (SDBR) on the radius of the SDBR core is studied. The SDBR reflection spectra were calculated by the method of spherical wave transfer matrices for different polarizations and different angular modal numbers of spherical waves. It is shown that if the core radius is much larger than the Bragg wavelength in the core substance, the width and spectral position of the stop-band are the same for both polarizations (TM and TE) of spherical waves and do not depend on the angular modal number of the spherical wave. If the core radius is less than several Bragg wavelengths in the core substance, a narrow dip appears in the reflection spectrum in the region of the stop-band for one polarization and some values of the angular modal number of spherical waves. It is shown that the reason for the appearance of this dip is the occurrence of a resonance in the SDBR quarter-wave layer closest to the core.