High-speed optical modulation based on carrier depletion in a silicon waveguide

Abstract

We present a high-speed and highly scalable silicon optical modulator based on the free carrier plasma dispersion effect. The fast refractive index modulation of the device is due to electric-field-induced carrier depletion in a Silicon-on-Insulator waveguide containing a reverse biased pn junction. To achieve high-speed performance, a travelling-wave design is used to allow co-propagation of electrical and optical signals along the waveguide. We demonstrate high-frequency modulator optical response with 3 dB bandwidth of ~20 GHz and data transmission up to 30 Gb/s. Such high-speed data transmission capability will enable silicon modulators to be one of the key building blocks for integrated silicon photonic chips for next generation communication networks as well as future high performance computing applications.

Attosecond‐precision ultrafast photonics

“…In particular, the rapidly growing field of silicon photonics will enable the integration of major optoelectronic components such as mode-locked lasers [27,122,123], high-speed modulators [124][125][126][127], and Si/Ge photodiodes [128,129] His research interests include classical and quantum noise in electronic and optical devices, femtosecond lasers and their applications in frequency metrology, precision timing distribution, high-speed signal processing, and attosecond science.…”

Ge-on-Si photonic devices for photonic-electronic integration on a Si platform

“…One of the basic modulators uses Mach-Zehnder interferometer (MZI) structure composed of two Si rib WGs embedding pn junction [62,63]. Because of the crystal symmetry of Si, there is no first-order electro-optic (EO) effect (Pockels effect), while the change in the refractive index in Si can be obtained with the free-carrier plasma effect induced by the high density of carriers [64].…”

High-speed Ge photodetector monolithically integrated with large cross-section silicon-on-insulator waveguide

“…This has fueled significant research and development work in this area in the past few years. [1][2][3][4][5][6][7][8][9][10][11] Many silicon-based active photonics components, such as high-speed modulators and Ge photodetectors [4][5][6][7][8][9][10] have been demonstrated on submicron waveguides. However, submicron SOI waveguides still suffer from high fiber coupling loss, high polarization dependent loss, and large waveguide birefringence and phase noise.…”