title: Interferometric optical isolator employing a nonreciprocal phase shift operated in a unidirectional magnetic field.
abstract: An interferometric optical isolator that employs a nonreciprocal phase shift was studied. The optical isolator consisted of an interferometer with distinct layer structures. A traveling light wave underwent distinct nonreciprocal phase shifts such that the optical isolator could be operated in a unidirectional magnetic field. The optical isolator, in which the waveguide had a HfO2 cladding layer in one of the arms, was designed at a wavelength of 1.55 microm. The propagation distance of the nonreciprocal phase shifter required for the isolator's operation was less than 1.5 mm. The device's total length was less than 2 mm. An optical isolator with distinct layer structures was fabricated and evaluated. An isolation ratio of approximately 9.9 dB was obtained in the unidirectional magnetic field.
authors.affiliation: Department of Electrical and Electronic Engineering, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, Japan. yokoi@wave.pe.titech.ac.jp
authors.forename: Hideki
authors.initials: H
authors.lastname: Yokoi
authors.forename: Yuya
authors.initials: Y
authors.lastname: Shoji
authors.forename: Etsu
authors.initials: E
authors.lastname: Shin
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Mizumoto