Microring-based Optical Isolator and Circulator with Integrated Electromagnet for Silicon Photonics

P. Pintus, D. Huang, C. Zhang, Y. Shoji, T. Mizumoto, and J.E. Bowers
Publication Image
Microscope image of the fabricated device with splits for various microring-waveguide coupling distances.
Publication Date
Publication Type
Journal/Conference Name
IEEE/OSA Journal of Lightwave Technology
vol. 35, no. 8, pp.1429-1437

In this study, we present optical isolators and circulators fabricated by bonding cerium-substituted yttrium iron garnet (Ce:YIG) on silicon microring resonators. A novel integrated electromagnet is fabricated by depositing a metal micro-strip on the bonded chip. We experimentally prove that it can be efficiently used to control the magnetic field needed to induce the nonreciprocal phase shift effect in the Ce:YIG. The fabricated devices exhibit extremely small footprint (≤ 70 μm) and can be packaged, eliminating the need of a large size permanent magnet. A large optical isolation of 32 dB and 11 dB is measured for the isolator and the circulator, respectively. Moreover, a two microring solution is also investigated to provide larger bandwidth and higher isolation. The proposed approach represents a promising solution for large-scale integration of nonreciprocal components in silicon photonics.

Research Areas
Silicon Photonics
Integration Technologies
Photonics Integrated Circuits
More Research Areas
Isolators & Circulators