title: MZI optical isolator with Si-wire waveguides by surface-activated direct bonding.
abstract: We fabricate a Mach-Zehnder interferometer-based optical isolator using a silicon-wire waveguide with magneto-optic garnet cladding using direct bonding techniques. Using Si-wire waveguides, the size of the device is greatly reduced from that of our previous device. We investigate surface-activated direct bonding with nitrogen plasma treatment, which shows better bonding results than oxygen plasma treatment. A large magneto-optic phase shift of 0.8π and an optical isolation of 18 dB are obtained at a wavelength of 1322 nm.
authors.affiliation: Department of Electrical and Electronic Engineering, Tokyo Institute of Technology, 2-12-1-S3-11 Ookayama, Tokyo 152-8552, Japan. shoji.y.ad@m.titech.ac.jp
authors.forename: Yuya
authors.initials: Y
authors.lastname: Shoji
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Ito
authors.forename: Yuya
authors.initials: Y
authors.lastname: Shirato
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Mizumoto