We report a hybrid integrated external cavity laser by butt coupling a quantum dot reflective semiconductor optical amplifier and a silicon-on-insulator chip. The device lasers at 1302 nm in the O-band, a wavelength regime critical to data communication systems. We measured 18 mW on-chip output power and over 50-dB side-mode suppression ratio. We also demonstrated open eye diagrams at 10 and 40 Gb/s.
Silicon photonics has attracted extensive attention in recent years as a promising solution for next generation high-speed, low energy consumption, and low cost data transmission systems. Although a few experiments indicated board-level and long haul communication capability, major and near-future application of silicon photonics is commonly seen as Ethernet at 100Gb/s and beyond, such as interconnects in data centers, where O-Band (near 1310 nm wavelength) has been standardized for its low fiber dispersion. However, almost all silicon photonics devices demonstrated up to date operate at C-Band (1530 nm to 1560 nm), the fiber loss and erbium amplification window, probably due to the wider availability of lasers and testing apparatus at this wavelength. Typical C-Band devices cannot operate at O-Band, thus the whole device library needs to be redesigned and recalibrated for O-Band applications. In this paper, we present an ultra compact, low loss, and low crosstalk waveguide crossing operating at O-Band. It is designed using the finite difference time domain method coupled with a particle swarm optimization. Device footprint is only 6 μm × 6 μm. The measured insertion loss is 0.19±0.02 dB across an 8-inch wafer. Cross talk is lower than -35 dB. We also report a second waveguide crossing with a 9 μm × 9 μm footprint with 0.017±0.005 dB insertion loss. Finally we summarize the performance of our overall O-Band device library, including low-loss waveguides, high-speed modulators, and photodetectors.
We have developed a CMOS-compatible Silicon-on-Insulator photonic platform featuring active components such as pi- n and photoconductive (MIM) Ge-on-Si detectors, p-i-n ring and Mach-Zehnder modulators, and traveling-wave modulators based on a p-n junction driven by an RF transmission line. We have characterized the yield and uniformity of the performance through automated cross-wafer testing, demonstrating that our process is reliable and scalable. The entire platform is capable of more than 40 GB/s data rate. Fabricated at the IME/A-STAR foundry in Singapore, it is available to the worldwide community through OpSIS, a successful multi-project wafer service based at the University of Delaware. After exposing the design, fabrication and performance of the most advanced platform components, we present our newest results obtained after the first public run. These include low loss passives (Y-junctions: 0.28 dB; waveguide crossings: 0.18 dB and cross-talk -41±2 dB; non-uniform grating couplers: 3.2±0.2 dB). All these components were tested across full 8” wafers and exhibited remarkable uniformity. The active devices were improved from the previous design kit to exhibit 3dB bandwidths ranging from 30 GHz (modulators) to 58 GHz (detectors). We also present new packaging services available to OpSIS users: vertical fiber coupling and edge coupling.
Silicon photonics has emerged as a promising material system for the fabrication of photonic devices as well as
electronic ones. The key advantage is that many electronic and photonic functions that up to now have only been
available as discrete components can be integrated into a single package. We present a silicon photonic platform that
includes low-loss passive components as well as high-speed modulators and photodetectors at or above 30 GHz. The
platform is available to the community as part of the OpSIS-IME MPW service.
Shared shuttle runs are an important factor of the microelectronics business ecosystem, allowing fabless semiconductor
companies to access advanced processes and supporting the development of new tools and processes. We report on the
creation and progress of a shared shuttle program for access to advanced silicon photonics optoelectronic platforms that
we expect will create a similar environment for the field of integrated photonics.
Silicon waveguides have, to date, largely been designed to operate near the telecommunication bands in the near
infrared. The mid-infrared (MIR) wavelengths, which range from two to twenty microns, are critical for a number of
application areas, including chemical bond spectroscopy and thermal imaging. We show results, using commercially
available silicon-on-sapphire wafers, for low-loss (4.0 dB/cm) waveguides and what we believe to be the first working
microresonators operating at wavelengths around 5.5 um in silicon guides with Q-values as high as 3.0 k. This talk will
discuss the applications for mid-infrared integrated photonics in the silicon system, particularly for sensing and nonlinear
Silicon nano-slot waveguides have proven to be useful for a variety of applications, including nonlinear optics,
biosensing, and electrooptic modulation. In particular, an electrooptic polymer clad, electrically contacted, strip-loaded
slot waveguide design has been shown to be particularly useful for high-bandwidth electrooptic modulators. One of the
significant challenges for many of the applications of these waveguides is the necessity of low waveguide losses. We
demonstrate the ability to fabricate single mode strip-loaded slot waveguides, with losses as low as 6.5 dB/cm, using
conventional stepper-based photolithography. Additionally, we discuss the benefits of an asymmetric slot waveguide
design and present improved losses as low as 2 dB/cm for both asymmetric strip-loaded slot waveguides and regular
asymmetric slot waveguides fabricated in a different photolithographic process.
This communication primarily deals with utilizing organic electro-optic (OEO) materials for the fabrication of active wavelength division multiplexing (WDM) transmitter/receiver systems and reconfigurable optical add/drop multiplexers (ROADMs), including the fabrication of hybrid OEO/silicon photonic devices. Fabrication is carried out by a variety of techniques including soft and nanoimprint lithography. The production of conformal and flexible ring microresonator devices is also discussed. The fabrication of passive devices is also briefly reviewed. Critical to the realization of improved performance for devices fabricated from OEO materials has been the improvement of electro-optic activity to values of 300 pm/V (or greater) at telecommunication wavelengths. This improvement in materials has been realized exploiting a theoretically-inspired (quantum and statistical mechanics) paradigm for the design of chromophores with dramatically improved molecular first hyperpolarizability and that exhibit intermolecular electrostatic interactions that promote self-assembly, under the influence of an electric poling field, into noncentrosymmetric macroscopic lattices. New design paradigms have also been developed for improving the glass transition of these materials, which is critical for thermal and photochemical stability and for optimizing processing protocols such as nanoimprint lithography. Ring microresonator devices discussed in this communication were initially fabricated using chromophore guest/polymer host materials characterized by electro-optic coefficients on the order of 50 pm/V (at telecommunication wavelengths). Voltage-controlled optical tuning of the pass band of these ring microresonators was experimental determined to lie in the range 1-10 GHz/V or all-organic and for OEO/silicon photonic devices. With new materials, values approaching 50 GHz/V should be possible. Values as high as 300 GHz/V may ultimately be achievable.
We demonstrate an electrically-tuned nematic liquid crystal (LC) infiltrated photonic crystal (PC) laser. The PC laser is encased between two transparent indium tin oxide (ITO) glass plates which serve as the modulating electrodes and also define the LC cell. Applying a voltage across the cell realigns the LC, modifies the laser cavity's optical path length, and blue-shifts the lasing wavelength. The measured tuning threshold voltage agrees well with the experimentally determined LC threshold voltage which confirms the tuning is due to the LC realignment at the onset of the LC's Freedericksz transition. Furthermore, the electrically-tuned PC laser also demonstrates the successful integration of nonlinear optical materials, electronics, and fluidics with PCs and suggests further integration with other materials will lead to photonic devices with increased functionality and utility.