Juthika Basak

Demonstration of a High Speed 4-Channel Integrated Silicon Photonics WDM Link with Hybrid Silicon Lasers

The demonstration of a 4λ×10Gbps Silicon Photonics CWDM link integrating all optical components, electronics and packaging technologies required for system integration is reported. Further demonstration of the link operating at 50Gbps, 4λ×12.5Gbps, is also shown.

Wavelength Division Multiplexing Based Photonic Integrated Circuits on Silicon-on-Insulator Platform

We review recent advances in the development of silicon photonic integrated circuits for high-speed and high-capacity interconnect applications. We present detailed design, fabrication, and characterization of a silicon integrated chip based on wavelength division multiplexing. In such a chip, an array of eight high-speed silicon optical modulators is monolithically integrated with a silicon-based demultiplexer and a multiplexer. We demonstrate that each optical channel operates at 25 Gb/s. Our measurements suggest the integrated chip is capable of transmitting data at an aggregate rate of 200 Gb/s. This represents a key milestone on the way for fabricating terabit per second transceiver chips to meet the demand of future terascale computing.

CMOS-compatible, athermal silicon ring modulators clad with titanium dioxide

We present the design, fabrication and characterization of athermal nano-photonic silicon ring modulators. The athermalization method employs compensation of the silicon core thermo-optic contribution with that from the amorphous titanium dioxide (a-TiO(2)) overcladding with a negative thermo-optic coefficient. We developed a new CMOS-compatible fabrication process involving low temperature RF magnetron sputtering of high-density and low-loss a-TiO(2) that can withstand subsequent elevated-temperature CMOS processes. Silicon ring resonators with 275 nm wide rib waveguide clad with a-TiO(2) showed near complete athermalization and moderate optical losses. Small-signal testing of the micro-resonator modulators showed high extinction ratio and gigahertz bandwidth.

Recent development in a high-speed silicon optical modulator based on reverse-biased pn diode in a silicon waveguide

We review the recent development of a high-speed silicon optical modulator based on electric-field-induced carrier depletion effect in a silicon-on-insulator waveguide containing a reverse-biased p–n junction. The device design, fabrication and characterization are presented. To obtain efficient optical modulation, we design a sub-micrometer size silicon waveguide phase shifter based on both semiconductor device modeling and photonic circuit modeling. By employing traveling-wave drive that allows co-propagation of electrical and optical signals along the waveguide, we demonstrate a high-frequency modulator with 3 dB optical response bandwidth of 30 GHz and data transmission up to 40 Gb s−1. Such a high-speed silicon modulator will be a key component for silicon-photonic-integrated circuits for future computing I/O applications.

Silicon Optical Modulator for High-speed Applications

We review silicon photonic technologies enabling low-cost photonic integrated circuits (PIC) for future optical interconnects. In particular, we discuss design, fabrication, and characterization of a high-speed silicon optical modulator capable of transmitting data up to 30 Gbps.

A Silicon Modulator Enabling RF Over Fiber for 802.11 OFDM Signals

We investigate the linearity properties of silicon modulators and show that, contrary to the traditional lithium niobate Mach-Zehnder modulators (MZMs), the third-order intermodulation distortion (IMD3) for silicon modulators is a function of the modulator bias point. The bias point for silicon modulators can be chosen to reduce the IMD3 well below that of standard lithium niobate MZMs. Given the cost and integration advantages of the silicon photonics technology, silicon modulators offer significant advantages for emerging radio over fiber applications. As an example, we examine, for the first time to our knowledge, a silicon modulator for converting analog 802.11 RF signals to the optical domain, achieving an error vector magnitude of -30 dB.

Developments in Gigascale Silicon Optical Modulators Using Free Carrier Dispersion Mechanisms

This paper describes the recent advances made in silicon optical modulators employing the free carrier dispersion effect, specifically those governed by majority carrier dynamics. The design, fabrication, and measurements for two different devices are discussed in detail. We present an MOS capacitor-based modulator delivering 10 Gbps data with an extinction ratio of ∼ 4 dB and a pn-diode-based device with high-speed transmission of 40 Gbps and bandwidth greater than 30 GHz. Device improvements for achieving higher extinction ratios, as required for certain applications, are also discussed. These devices are key components of integrated silicon photonic chips which could enable optical interconnects in future terascale processors.

High-Speed Silicon Modulator for Future VLSI Interconnect

We demonstrate a silicon optical modulator capable of transmitting data at a bit rate up to 40 Gbps. Such a high-speed modulator enables integrated silicon photonic chips for future high data streams VLSI interconnect applications.

200 Gbps photonic integrated chip on silicon platform

We report a silicon photonic integrated circuit that contains a fast silicon optical modulator array and wavelength multiplexer/de-multiplexer. We demonstrate high-speed data transmission with an aggregate data rate of 200 Gbps on a single silicon chip.

Recent advances in high speed silicon optical modulator

High-speed silicon optical modulator is one of key components for integrated silicon photonic chip aiming at Tb/s data transmission for next generation communication networks as well as future high performance computing applications. In this paper we review the recent development of the silicon modulator. In particular, 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 traveling-wave design is employed 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. We also highlight the future device optimization for 40 Gb/s and beyond.