Demonstration of an On-Chip TE-Mode Optical Circulator

In this paper, an on-chip optical circulator on the InP-membrane-on-Si (IMOS) platform is demonstrated. The circulator is composed of two multi-mode interferometers (MMIs), four polarization converters (PCs), and a Cerium-doped Yttrium Iron Garnet (Ce:YIG) die. The Ce:YIG die is adhesively bonded on the InP membrane via a 125-nm thin bonding layer. Nonreciprocal phase shift (NRPS) is employed in the presence of a transverse magnetic field. The device works as a 4-port optical circulator with a maximum optical isolation of 27.0 dB and a minimum optical isolation of 18.6 dB for the TE mode. The measured optical isolation bandwidth is 0.12 nm. Two methods are proposed in order to improve the optical isolation bandwidth.

Automated summary

This paper demonstrates an on-chip optical circulator on the InP-membrane-on-Si (IMOS) platform. The circulator is composed of two multi-mode interferometers (MMIs), four polarization converters (PCs), and a Cerium-doped Yttrium Iron Garnet (Ce:YIG) die. The Ce:YIG die is bonded on the InP membrane via a thin bonding layer. Nonreciprocal phase shift (NRPS) is employed using a transverse magnetic field. The device functions as a 4-port optical circulator and achieves a maximum optical isolation of 27.0 dB and a minimum optical isolation of 18.6 dB for the TE mode. The proposed methods aim to improve the optical isolation bandwidth.