Small magnetless integrated optical isolator using a magnetized cobalt ferrite film

IEICE Electronics Express

article

Mario Alberto Serrano-Núñez¹  Yuya Shoji¹  Tetsuya Mizumoto¹ 

[1] Department of Electrical and Electronic Engineering, Tokyo Institute of Technology;FIRST, Tokyo Institute of Technology

关键词: silicon photonics;    optical isolators;    micro ring resonators;    magneto-optical materials;    cobalt ferrite films;   

DOI  :  10.1587/elex.18.20210500

学科分类：电子、光学、磁材料

来源: Denshi Jouhou Tsuushin Gakkai

【 摘 要 】

We experimentally demonstrated a silicon optical isolator using a monolithically integrated cobalt ferrite (CFO) film as magneto-optical material, achieving an isolation ratio of 9.6dB near 1550nm wavelength. By virtue of the large Faraday rotation coefficient of CFO, the device has a compact footprint comparing to the current yttrium iron garnet-based isolators. Furthermore, we demonstrated self-biased isolation by the strong remanence of CFO films, eliminating the tedious demand of an external magnet. Cobalt ferrite represents a potential alternative approach to yttrium iron garnets to realize a practical device for on-chip isolation in silicon photonic integrated circuits because of the small footprint.

【 授权许可】

CC BY