Optimization of high-Q Bragg reflector resonator

In this paper, we present a method of designing a Bragg reflector structure, using a simple non-Maxwellian model. This allows us to obtain an unloaded Q-factor of 350,000 with a one-layer Bragg reflector resonator at room temperature and at 10GHz, using sapphire (ε_r=9.394, tanδ=5.9*10^-6). Also, we noticed that for high permittivity materials the requirement of loss tangent is reduced to obtain the same Q-factor for a lower permittivity material. Finally we report the experimental results on a sapphire with a one-layer-Bragg reflector. The Q-factor of 190,000 was obtained at a frequency of 8.8 GHz.