학술논문

Slow-Light-Enhanced Silicon Optical Modulators Under Low-Drive-Voltage Operation
Document Type
Periodical
Source
IEEE Photonics Journal IEEE Photonics J. Photonics Journal, IEEE. 4(5):1306-1315 Oct, 2012
Subject
Engineered Materials, Dielectrics and Plasmas
Photonics and Electrooptics
Optical waveguides
Silicon
Optical modulation
Phase shifters
CMOS integrated circuits
Insertion loss
Slow light
photonic band-gap structures
silicon nanophotonics
optical interconnects
Language
ISSN
1943-0655
1943-0647
Abstract
The integration of nanophotonics components with advanced complementary metal–oxide–semiconductor (CMOS) electronics requires drive voltages as low as 1 V for enabling next-generation CMOS electrophotonics transceivers. Slow-light propagation has been recently demonstrated as an effective mechanism to enhance the modulation efficiency in free-carrier-based electrooptical silicon modulators. Here, we exploit the use of slow light to reduce the driving voltage of carrier-depletion-based Mach–Zehnder modulators. The slow-light phase shifter consists of a p-n junction positioned in the middle of a corrugated waveguide. A modulation efficiency as high as $V_{\pi}L_{\pi} \sim 0.6 \ \hbox{V}\cdot \hbox{cm}$ is achieved, thus allowing data transmission rates up to 10 Gb/s with a 1.5-$ \hbox{V}_{\rm pp}$ drive voltage and an insertion loss of $\sim$ 12 dB. The influence of the drive voltage on the modulation speed as well as the variation of the insertion losses with a group index is also analyzed and discussed.