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Updated: May 25, 2026

Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Mode junction photonics with a symmetry-breaking arrangement of mode-orthogonal heterostructures
Sunkyu Yu1, Xianji Piao, Sukmo Koo
1School of EECS, Seoul National Univ., Seoul, South Korea.
Abstract:
Junction structures provide the foundation of digital electronics and spintronics today. An equivalent, a photonic junction to achieve systematic and drastic control of photon flow is currently missing, but is mandatory for serious all-optical signal processing. Here we propose a photonic junction built upon mode-orthogonal hetero-structures, as a fundamental structural unit for photonic integrated circuits. Controlling the optical potential of mode-orthogonal junctions, the flow of photons can be dynamically manipulated, to complete the correspondence to the electronic junction structures. Of the possible applications, we provide examples of a photonic junction diode and a multi-junction half-adder, with exceptional performance metrics. Highly directional (41dB), nearly unity throughput, ultra-low threshold-power, high quality signal regeneration at 200Gb/s, and all-optic logic operations are successfully derived with the self-induced, bi-level dynamic mode-conversion process across the junction.
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