Q-factor in 2D photonic crystal microcavities with low refractive index

摘要

In this work, we theoretically investigate the L3 cavity with three missing holes in the center. The Photonic cavities have an ultra-low index contrast and are fabricated by SiO₂/ZrO₂ or SiO₂/TiO₂ in which the refractive index varies in the range of 1.51 to 1.58 at λ =1.55 μm. We show that cavity modes can be differently tuned depending on the size and the position of the first hole adjacent to the cavity. A photonic microcavity with a high Q factor of 10³ in low index contrast is demonstrated. We demonstrate that the calculated Q factor for the designed cavity increases by a factor of 13 relative to that for a cavity without displaced and reduced air holes. These microcavities with low refractive index may serve as a fundamental structure in a variety of ultra high telecommunication devices such as optical filters, sensors and modulators in the future.