A5000891326- Photonic and Optical Devices
- Optical Network Technologies
- Neural Networks and Reservoir Computing
- Semiconductor Lasers and Optical Devices
- Advanced Memory and Neural Computing
- Photonic Crystals and Applications
- Neural Networks and Applications
- Terahertz technology and applications
- Carbon Nanotubes in Composites
- Mechanical and Optical Resonators
- Semiconductor Quantum Structures and Devices
- Nanotechnology research and applications
- Topological Materials and Phenomena
- Advanced Photonic Communication Systems
- Silicon Nanostructures and Photoluminescence
- Optical Coatings and Gratings
- Nanowire Synthesis and Applications
- Semiconductor materials and devices
- Thermal Radiation and Cooling Technologies
NTT (Japan)
2019-2024
The University of Tokyo
2018
We demonstrate photonic reservoir computing (RC) utilizing cross-gain modulation (XGM) in a membrane semiconductor optical amplifier (SOA) on Si platform. The SOA's features of small active volume and strong confinement enable low-power nonlinear operation the reservoir, with 101-mW-scale power consumption 102-µW-scale input power. is about an order magnitude lower than that conventional SOAs exhibit saturable nonlinearity. XGM-based configured by injecting delayed feedback signal into SOA...
Ultrashort-distance optical interconnects are becoming increasingly important due to continuous improvements in servers and high-performance computers. As light sources such interconnects, directly modulated semiconductor lasers with an ultrasmall active region promising. In addition, using Si waveguides is provide low loss links functions as wavelength filtering switching. this paper, we demonstrate a wafer-scale heterogeneous integration of lambda-scale embedded active-region...
We have investigated the electronic structures of metallic carbon nanotube quantum dots (CNT QDs) by terahertz-induced photocurrent spectroscopy. Sharp peaks due to intersublevel transitions in CNT QDs are observed at sublevel energy spacings expected from linear band dispersion. The line width peak is as narrow 0.3 meV and governed tunnel coupling with electrodes, indicating that scattering time electrons present CNTs comparable or longer than 10 ps. observation a sharp absorption bare...
We propose and demonstrate reservoir computing (RC) by all-optical nonlinear processing based on cross-gain modulation (XGM) in III-V membrane semiconductor optical amplifiers (SOAs) a Si Mach-Zehnder interferometer (MZI). In the proposed configuration, two counter-propagating signals are input into SOA-MZI from opposite ports, where they nonlinearly modulate each other via XGM, output to ports. This realizes an on-chip XGM-based processor that separately takes returns signals, not requiring...
We demonstrate reservoir computing using a fiber delay line and membrane semiconductor optical amplifier on Si. Thanks to its small active volume low fiber-coupling loss, the consumes only 43 mW for nonlinear activation.
We demonstrate 40-Gbps, 16.6-fJ/bit direct modulation of a one-dimensional photonic-crystal (1D-PhC) nanolaser on SiO 2 /Si with 180-μA bias current. Very strong optical confinement in the laterally-current-injected 1D-PhC nanocavity is key for high-speed, high-modulation-efficiency operation.
We solve the Santa-Fe prediction task with reservoir computing utilizing cross-gain modulation in membrane semiconductor optical amplifiers (SOAs). SOAs are heterogeneously integrated on each arm of Si-based Mach-Zehnder interferometer to spatially separate input/output ports.
A membrane MZM integrated with SOAs on Si is utilized for reservoir computing. The are asymmetrically driven to exploit cross-phase modulation (XPM), which enhances the responsivity and improves pulse train lifetime.
One-dimensional photonic-crystal lasers with 2.5-μm-long buried active regions are fabricated on SiO 2 /Si substrate. The rib-shaped structure enables lateral-current-injection, high-Q cavity, and strong optical confinement. device exhibits 13.0-μA threshold current 28.0% external differential-quantum-efficiency.
Increasing power consumption in the data center has become a social issue. In order to reduce consumption, introduction of optical technology into ultra-short range is highly desired. For this purpose, we are developing membrane photonic devices, which heterogeneously integrated with Si devices.
Summary form only given. We have fabricated an InP-based lambda-scale embedded active-region photonic-crystal (LEAP) laser with extremely short length of just the lattice constant (~430 nm) photonic crystal (PhC). achieved lasing a low threshold current 8.7 μA at room temperature. Still, this is rather high compared those two ( 4.9 μA) or three times 6.6 longer active regions. The dependence static characteristics on discussed, which infers that improvement in injection structure necessary...
We implemented an on-chip photonic reservoir computer using integrated circuits and applied it to coherent optical communications. Our linear nonlinear processing platform is suitable for non-von-Neumann computing engines.
A membrane laser on high-thermal-conductivity SiC exhibits a 42-GHz relaxation oscillation frequency because of the large optical confinement and heat dissipation. Photon-photon resonance increases bandwidth to 108 GHz capable 256-Gbit/s PAM-4 signal transmission.
A membrane laser on high-thermal-conductivity SiC exhibits a 42-GHz relaxation oscillation frequency because of the large optical confinement and heat dissipation. Photonphoton resonance increases bandwidth to 108 GHz capable 256-Gbit/s PAM-4 signal transmission.
We fabricate an 8-ch 160-nm-range membrane laser array with selectively grown InGaAlAs-MQWs on a thin InP layer SiO 2 /Si. By controlling the material gain peak and lasing wavelength, all lasers exhibit 32-Gbit/s NRZ direct modulation.
We describe directly modulated membrane lasers on high-thermal-conductivity SiC exhibiting a 42-GHz f <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</inf> and intrinsic 60-GHz bandwidth, thanks to the high optical confinement low device thermal resistance. Utilizing photon-photon resonance effect at 95 GHz, we demonstrate 108-GHz bandwidth 132-Gbit/s NRZ modulation.