volume | PIER Journals

Abstract

An ultra-compact isolator based on the integration of aluminum-substituted cobalt ferrite films with magneto-optical activity to a silicon microring resonator is suggested. The strong remanent magnetization of the employed magneto-optical material allows the operation of the device without any external magnetizing elements, and the device footprint is only 150 μm². A prototype chip has been fabricated using conventional processes compatible with the silicon on an insulator platform, and a maximum isolation ratio of 7 dB at the 1557.6 nm wavelength has been achieved. To the best of our knowledge, this is the most compact photonic isolator demonstrated to date, and it is suitable for all-optical circuits with extremely high integration density.

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Dr. Gianni Portela

Dr. Yisheng Ni

Dr. Kotaro Sato

Dr. Yuya Shoji

Dr. Hugo Enrique Hernandez-Figueroa