Novel nonmagnetic 30-dB traveling-wave single-sideband optical isolator integrated in III/V material

• Published in: IEEE journal of selected topics in quantum electronics Vol. 11; no. 2; pp. 417 - 421
• Main Authors: Bhandare, S., Ibrahim, S.K., Sandel, D., Hongbin Zhang, Wust, F., Noe, R.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2005; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Amplitudes; Electrooptic modulators; Insertion loss; Integrated optical devices; Integrated optics; Isolators; Magnetic materials; Materials selection; Modulators; Noise levels; optical isolator; Optical losses; Optical materials; Optical modulation; Optical waveguides; Phase shift keying; Quantum electronics; Radio frequency; Ripples; traveling-wave (TW) devices
• ISSN: 1077-260X; 1558-4542
• DOI: 10.1109/JSTQE.2005.845620

Various attempts have been made to fabricate waveguide-type isolators in III/V material by implanting magnetic materials, but none of them has so far resulted in a commercial product. Here, we report for first time on an integrated optical isolator implemented in III/V material. It consists of a single-sideband electrooptic modulator where traveling electrical waves make the transmission direction-dependent. Isolation is 30 dB, excess insertion loss is 8 dB. Residual rms ripple is 7% for peak-to-peak RF driving amplitudes of 3.5 V at 4.0 GHz. The estimated transmission penalty for 40 Gb/s return-to-zero differential phase shift keying (RZ-DPSK) signals is 0.2 dB (0 dB measured).