Yasuhiko Ishikawa

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Group IV lasers are expected to revolutionize chip-to-chip optical communications in terms of cost, scalability, yield, and compatibility to the existing infrastructure of silicon industries for mass production. Here, we review the current state-of-the-art developments of silicon and germanium light sources toward monolithic integration. Quantum confinement(More)
By way of a brief review of Si photonics technology, we show that significant improvements in device performance are necessary for practical telecommunications applications. In order to improve device performance in Si photonics, we have developed a Si-Ge-silica monolithic integration platform, on which compact Si-Ge-based modulators/detectors and(More)
We propose an approach for tuning a gain spectrum of semiconductor lasers under temperature fluctuations, where the heat-induced effect is dynamically compensated using a mechanical stressing. By stressing GaAs/Ge/Si microbeams, emission wavelength tuning is experimentally demonstrated for the overlying GaAs layers as a proof-of-concept, and the results are(More)
(2015) Whispering gallery mode resonances from Ge micro-disks on suspended beams. Ge is considered to be one of the most promising materials for realizing full monolithic integration of a light source on a silicon (Si) photonic chip. Tensile-strain is required to convert Ge into an optical gain material and to reduce the pumping required for population(More)
Three-dimensional structures of microelectro-mechanical systems (MEMS)-based Ge waveguide on a Si beam were fabricated for dynamic tuning of the fundamental absorption edge of Ge by external stressing. The application of various amounts of external forces up to 1 GPa onto the Si beam shows clear red-shifts in the absorption edge of Ge waveguides on the Si(More)
Si photonics has attracted much interest over the last decade as it allows integration of photonic and electronic devices on a small Si chip, providing high-capacity, energy-efficient, and cost-effective optical interconnects. Active optical cables based on Si photonics are now commercially available for rack-to-rack interconnects in supercomputers and data(More)
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