Discovery of Bragg confined hybrid modes with high Q factor in a hollow dielectric resonator

The authors report on observation of Bragg confined mode in a hollow cylindrical dielectric cavity. A resonance was observed at 13.4 GHz with an unloaded Q factor of order 2x10(5), which is more than a factor of 6 above the dielectric loss limit. Previously, such modes have only been realized from pure transverse electric modes with no azimuthal variations and only the E-phi component. From rigorous numeric simulations, it is shown that the mode is a hybrid mode with nonzero azimuthal variations and with dominant E-r and E-phi electric field components and H-z magnetic field component. (c) 2007 American Institute of Physics.