Silicon is the most diffused material for microelectronic industry and, in recent times, it is becoming more and more widespread in integrated optic and optoelectronic fields. We present the thermo-electro-optical analysis of an integrated waveguide-vanishing-based optical modulator based on free-carrier dispersion effect, realizable on standard SOI wafer. The optical behavior is based on the vanishing of the lateral confinement in the rib region, and consequent cut-off of the propagating mode. Results show that an optical modulation depth close to 100% can be reached with a bandwidth of about 154 MHz. Smart electrical driving, that is an injection overdrive of a few volts for a very short time, allows to reach total ON-OFF switching time of about 860 ps. For that bias scheme the fall transient is then limiting the whole dynamic and the resulting bit rate in a pure digital modulation scheme is about 1.2 Gb/s.

Date Published: 5 June 2007
PDF: 8 pages
Proc. SPIE 6593, Photonic Materials, Devices, and Applications II, 65931N (5 June 2007); doi: 10.1117/12.722358

Published in SPIE Proceedings Vol. 6593:
Photonic Materials, Devices, and Applications II
Ali Serpengüzel; Gonçal Badenes; Giancarlo C. Righini, Editor(s)