We report designs for a silicon-on-insulator (SOI) onedimensional (ID) photonic crystal (PhC) nanocavity with modulated modegap barriers based on the lowest dielectric band. These cavities have an ultrahigh theoretical quality factor (Q) of 107-108 while maintaining a very small modal volume of 0.6-2.0 (λ/n)3, which are the highest Q for any nanocavities with SiO2 under-cladding. We have fabricated these SOI 1DPhC cavities and confirmed that they exhibited a Q of 3.6×10 5, which is also the highest measured Q for SOI-type PhC nanocavities. We have also applied the same design to ID PhC cavities with air claddings, and found that they exhibit a theoretical quality factor higher than 109. The fabricated air-cladding ID Si PhC cavities have showed a quality factor of 7.2×105, which is close to the highest Q value for ID PhC cavities.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics