Frozen Mode in an Asymmetric Serpentine Optical Waveguide. Issue 9 (10th May 2022)

• Record Type: Journal Article
• Authors: Herrero-Parareda, Albert; Vitebskiy, Ilya; Scheuer, Jacob; Capolino, Filippo
• Is Part Of: Advanced photonics research. Volume 3:Issue 9(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-10
• Subjects: frozen modes -- serpentine optical waveguides -- slow light -- stationary inflection points; Photonics -- Periodicals; 621.36505
• DOI: 10.1002/adpr.202100377
• Languages: English
• ISSNs: 2699-9293

Abstract

Abstract : The existence of a frozen mode in a periodic serpentine waveguide with broken longitudinal symmetry is demonstrated numerically. The frozen mode is associated with a stationary inflection point (SIP) of the Bloch dispersion relation, where three Bloch eigenmodes collapse on each other, as it is an exceptional point of order three. The frozen mode regime is characterized by vanishing group velocity and enhanced field amplitude, which can be very attractive in various applications including dispersion engineering, lasers, and delay lines. Useful and simple design equations that lead to realization of the frozen mode by adjusting a few parameters are derived. The trend in group delay and quality factor with waveguide length that is peculiar of the frozen mode is shown. The symmetry conditions for the existence of exceptional points of degeneracy associated with the frozen mode are also discussed. Abstract : An asymmetric serpentine optical waveguide (ASOW) with broken longitudinal symmetry displays a frozen mode associated with a stationary inflection point (SIP), which is a third‐order exceptional point of degeneracy (EPD). The frozen mode regime is characterized by vanishing group velocity, enhanced field amplitude, and a peculiar group delay and quality factor cubic trend with waveguide length.