Observation of slow light in glide-symmetric photonic-crystal waveguides

Chirag Murendranath Patil, Guillermo Arregui, Morten Mechlenborg, Xiaoyan Zhou, Hadiseh Alaeian, Pedro David García, Søren Stobbe*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

67 Downloads (Pure)


We report optical transmission measurements on suspended silicon photonic-crystal waveguides, where one side of the photonic lattice is shifted by half a period along the waveguide axis. The combination of this glide symmetry and slow light leads to a strongly enhanced chiral light-matter interaction but the interplay between slow light and backscattering has not been investigated experimentally in such waveguides. We build photonic-crystal resonators consisting of glide-symmetric waveguides terminated by reflectors and use transmission measurements as well as evanescent coupling to map out the dispersion relation. We find excellent agreement with theory and measure group indices exceeding 90, implying significant potential for applications in slow-light devices and chiral quantum optics. By measuring resonators of different length, we assess the role of backscattering induced by fabrication imperfections and its intimate connection to the group index.

Original languageEnglish
JournalOptics Express
Issue number8
Pages (from-to)12565-12575
Publication statusPublished - 11 Apr 2022


Dive into the research topics of 'Observation of slow light in glide-symmetric photonic-crystal waveguides'. Together they form a unique fingerprint.

Cite this