https://scholarsarchive.byu.edu/facpub/894/
"Air-Trench Splitters for Ultra-Compact Ring Resonators in Low Refracti" by Seunghyun Kim, Gregory...
We demonstrate air-trench splitters in low index contrast perfluorocyclobutyl (PFCB) waveguides. Splitters are fabricated by etching 800 nm wide high aspect...