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Updated: Feb 10, 2026
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
One-way edge modes in a photonic crystal of semiconductor at terahertz frequencies
Lingjuan He1, Qian Shen1, Jie Xu1
1Institute of Space Science and Technology, Nanchang University, Nanchang, 330031, China.
Abstract:
Electromagnetic edge mode in a photonic crystal (PhC), which is a square array of semiconductor rods in air, is theoretically investigated for terahertz frequencies. In the PhC, gyroelectric anisotropy is introduced in the semiconductor rods by applying an external magnetic field and consequently, a degeneracy point, at which two dispersion surfaces intersect, is lifted and a new band gap is created. The edge mode sustained by the PhC possesses the character of one-way propagation, and it even can be immune to backscattering at large defect on the wavelength scale and 90° sharp bend. The properties of the one-way mode are closely dependent on the cladding layer structure of the PhC.
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