Continuously tunable delay line based on SOI tapered Bragg gratings.

Technische Universität Berlin, Fachgebiet Hochfrequenztechnik, Berlin, Germany.
Optics Express (Impact Factor: 3.53). 05/2012; 20(10):11241-6. DOI: 10.1364/OE.20.011241
Source: PubMed

ABSTRACT The realization of an integrated delay line using tapered Bragg gratings in a drop-filter configuration is presented. The device is fabricated on silicon-on-insulator (SOI) rib waveguides using a Deep-UV 248 nm lithography. The continuous delay tunability is achieved using the thermo-optical effect, showing experimentally that a tuning range of 450 ps can be obtained with a tuning coefficient of -51 ps/°C. Furthermore the system performance is considered, showing that an operation at a bit rate of 25 Gbit/s can be achieved, and could be extended to 80 Gbit/s with the addition of a proper dispersion compensation.

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