A5025612402- Photonic and Optical Devices
- Semiconductor Lasers and Optical Devices
- Optical Network Technologies
- Advanced Photonic Communication Systems
- Thin-Film Transistor Technologies
- Magnetic properties of thin films
- Optical Wireless Communication Technologies
- Advanced Memory and Neural Computing
- Semiconductor materials and devices
- Carbon Nanotubes in Composites
- Semiconductor Quantum Structures and Devices
- Ferroelectric and Negative Capacitance Devices
- Surface and Thin Film Phenomena
- Quantum and electron transport phenomena
- Graphene research and applications
- Semiconductor materials and interfaces
- Electrical and Thermal Properties of Materials
- Molecular Junctions and Nanostructures
- Neural Networks and Applications
- Advanced optical system design
- Advanced Power Amplifier Design
- Electric Power Systems and Control
- Organic Electronics and Photovoltaics
- GaN-based semiconductor devices and materials
- Analog and Mixed-Signal Circuit Design
NTT (Japan)
2015-2024
Tokyo University of Science
2011-2013
Kobe Steel (Japan)
2012
Osaka University
2003-2006
The modulation speed of light-emitting diodes (LEDs) must be increased to improve the speed, increase bandwidth, and miniaturize hardware visible light communication (VLC) systems. LED is limited by remaining carriers that remain in depletion capacitance. In this paper, we evaluate optical transmission rate for an driver first time sweeping out a GaN-based VLC system. fabricated using discrete GaAs FETs passive elements on board. An experiment performed. experimental results demonstrate...
We report on space-division multiplexing (SDM) transmissions of up to 400 Gb/s over a homogeneous four-core fiber using discrete multitone (DMT) modulation for intra-datacenter applications and 200/400 GbE links. The transmission system is enabled by compact, SDM-channel scalable, multi-core (MCF) pluggable, energy-efficient SDM transmitter composed 4-channel 1.3-μm membrane directly modulated laser (DML) array-on-silicon integrated with fiber-bundle type fan-in loss less than 1 dB...
This paper presents a four-level pulse amplitude modulation (PAM4) driver IC that can compensate for the nonlinearity of extinction curve an electroabsorption modulator (EAM). The was designed and fabricated by using our InP HBT technology ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$f_{t}\,= \,{\text{290 GHz}}$</tex-math> </inline-formula> , notation="LaTeX">$f_{{\rm{max}}}\,= \,{\text{320 ). To...
We describe a new multicore fiber (MCF) receptacle for space division multiplexing (SDM) based transceiver applications, in which we integrated compact fiber-bundle type fanin/fan-out device directly connecting MCF to LDs and PDs.We design the length of fan-out fibers taking their bending stress into account achieve configuration with smaller footprint.With proposed receptacle, develop 100 Gb/s SDM transmitter on four-channel, 1.3 µm membrane laser array Si, spot-size convertor (SSC) using...
Silicon photonics is a key technology for constructing large-scale photonic integrated circuits (PICs) because it enables wafer processes with high uniformity and quality.To further improve device characteristics, heterogeneous integration of III-V compound semiconductors that provide optical gain, modulation efficiency, non-linearity desired.This paper describes the membrane semiconductor devices have similar structure including thickness refractive index.These efficient coupling Si...
We describe a multicore-fiber LC receptacle with compact fan-in/fan-out as new transceiver interface for connecting LDs and PDs. achieve low-loss coupling the between 4-core MCF laser array.
A 4-channel wire-bond-free 3D-stacked transmitter module consisting of a 65-nm CMOS cascode shunt LD driver, 1.3-μm LD-array-on-Si, and LTCC interposer achieves simultaneous 25-Gbps error-free transmission over 1.2-km-long SSMF, with power consumption 2.67 mW/Gbps.
We investigate the electronic and magnetic properties of a metallic (3, 3) single-walled carbon nanotube (SWCNT) filled with linear Fe nanowire, based on ab initio spin-polarized density functional theory. find that in stable structure Fe-filled 3), (5, 0) SWCNTs exhibit semiconducting properties, nanowires lose their moment, while (4, 4), 5), (6, 6), having larger radius are metallic, show moments.
The transmission capacity of Ethernet has grown rapidly. Advanced multilevel modulation schemes, such as a 4-level pulse amplitude (PAM4), are being investigated to their suitability for next-generation 400GbE. demand is now high transmitter front-end with low-power laser diode (LD) driver that applicable modulations. To meet this demand, we devised linear shunt LD constructing supports PAM4. was designed and fabricated by using our InP HBT technology (ft = 290 GHz, fmax 320 GHz). power...
A low-power compact 4-channel transmitter consisting of a 65-nm CMOS cascode shunt LD driver and flip-chip-bonded 1.3-μm LD-array-on-Si achieves 25-Gbps 2-km-long SSMF error-free operation for each channel, with power consumption 1.37 mW/Gbps.
Optical interconnections, which apply optical technology to short-range communications on printed circuit boards in datacenters, are being studied for faster information processing infrastructure and lower power consumption.In this article, we introduce membrane-type directly modulated lasers silicon (Si) substrates.These can be integrated with Si photonic devices driven by complementary metal oxide semiconductor-based drivers low consumption.
We devised a PAM4 driver IC that can compensate for the nonlinearity of extinction curve an electroabsorption modulator (EAM). The was designed and fabricated by using our InP HBT technology (f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">t</sub> = 290 GHz, f xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> 320 GHz). adjust modulation voltage swing each intensity level to obtain clear eye openings in optical domain. results showed output...
This article presents a 2-channel 4-level pulse amplitude modulation (PAM4) transmitter front-end consisting of PAM4 shunt laser diode (LD) driver and flip-chip-bonded 1.3-μm LD array-on-Si that has the highest power efficiency yet reported for front-ends. The was designed fabricated using 65-nm CMOS technology, membrane technology. To decrease consumption, does not use high-speed digital-to-analog converter (DAC) or linear generating signals. Instead, to generate clear signals, incorporates...
We are studying the development of very compact next-generation optical transceivers by using integrated design techniques photonics-electronics implementation.We introduce in this article used to analog circuits with low power for implementation.
Electron traps in the channel region of amorphous In–Ga–Zn–O (a-IGZO) thin film transistors (TFTs) were evaluated using capacitance transient responses from (50 nm) metal-oxide-semiconductor diodes. It was found that carrier transport mainly dominated by conduction band tail states. The trap density a-IGZO deposited at 5 mTorr higher than 1 mTorr, providing direct evidence layer decreased decreasing sputtering pressure during IGZO deposition. defect states with activation energies ∼0.2 eV...