Exceptional Points of Degeneracy in Waveguides with or without Loss and Gain

• Published in: 2022 Sixteenth International Congress on Artificial Materials for Novel Wave Phenomena (Metamaterials) pp. 326 - 328
• Main Authors: Nikzamir, A., Furman, N., Herrero, A., Mealy, T., Capolino, F.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 12-09-2022
• Subjects: Antenna measurements; Delay lines; Distributed amplifiers; Metamaterials; Oscillators; Sensor phenomena and characterization; Slow light
• DOI: 10.1109/Metamaterials54993.2022.9920772

There are two kinds of exceptional points of degeneracy (EPD) in waveguides: those in the absence of loss and gain, related to slow light, and those where the waveguide has distributed gain and/or loss. Here, we discuss both kinds and highlight their differences. We show EPDs of order 2, 3, 4 and 6 in waveguides supporting two or three modes in each direction, and how the coalescence parameter is a good tool to measure the degree of degeneracy by measuring the angle between the eigenvectors (polarization states). In highlighting the differences between the two kinds of EPDs, we also show different sets of applications, which include sensors, delay lines, distributed amplifiers, antennas, and oscillators.