A5058351875- Photonic and Optical Devices
- Photonic Crystals and Applications
- Semiconductor Lasers and Optical Devices
- Advanced Fiber Laser Technologies
- Mosquito-borne diseases and control
- Industrial Vision Systems and Defect Detection
- Plant Disease Resistance and Genetics
- Optical Coatings and Gratings
- Advanced Machining and Optimization Techniques
- Advanced Surface Polishing Techniques
- Semiconductor materials and devices
- Enzyme Production and Characterization
- Advanced Memory and Neural Computing
- Advancements in Semiconductor Devices and Circuit Design
- Optical Network Technologies
- Advanced machining processes and optimization
- Spider Taxonomy and Behavior Studies
- Atomic and Molecular Physics
- Molecular Junctions and Nanostructures
- Advanced Measurement and Metrology Techniques
- Advanced Fiber Optic Sensors
- Carbon Nanotubes in Composites
- Neural Networks and Applications
- Surface Roughness and Optical Measurements
- Endodontics and Root Canal Treatments
Yamaha (Japan)
2025
Kyoto University
2016-2024
Kyoto Katsura Hospital
2018-2024
Canon (Japan)
2021-2022
Furukawa Electric (Japan)
2018-2021
The University of Tokyo
2009-2021
College of Industrial Technology
2007-2021
Metropolitan College
2006-2021
Sony Corporation (United States)
2021
Kyushu University
2004-2019
Realizing large-scale single-mode, high-power, high-beam-quality semiconductor lasers, which rival (or even replace) bulky gas and solid-state is one of the ultimate goals photonics laser physics. Conventional high-power however, inevitably suffer from poor beam quality owing to onset many-mode oscillation1,2, and, moreover, oscillation destabilized by disruptive thermal effects under continuous-wave (CW) operation3,4. Here, we surmount these challenges developing photonic-crystal...
Realization of one-chip, ultra-large-area, coherent semiconductor lasers has been one the ultimate goals laser physics and photonics for decades. Surface-emitting with two-dimensional photonic crystal resonators, referred to as photonic-crystal surface-emitting (PCSELs), are expected show promise this purpose. However, neither general conditions nor concrete structures realize 100-W-to-1-kW-class single-mode operation in PCSELs have yet be clarified. Here, we analytically derive...
Abstract Light detection and ranging (LiDAR) is a key technology for smart mobility of robots, agricultural construction machines, autonomous vehicles. However, current LiDAR systems often rely on semiconductor lasers with low-quality, large-divergence, asymmetric beams, requiring high-precision integration complicated lens to reshape the beam. Also, due broad linewidth large temperature dependence their lasing spectrum, bandpass filter bandwidth must be used in front detector, so detected...
Ultrafast dynamics in nanophotonic materials is attracting increasing attention from the perspective of exploring new physics fundamental science and expanding functionalities various photonic devices. In general, such induced by external stimuli as optical pumping or voltage application, which becomes more difficult power to be controlled larger owing increase energy required for control. Here, we demonstrate a concept self-evolving crystal, where spatial profile band dynamically changed...
Realization of single-mode, high-power and high-beam-quality (namely, high-brightness) semiconductor lasers, which can rival or even replace bulky lasers such as gas, solid, fiber is one the ultimate goals laser physics photonics. The demand for single-mode high-brightness increasing a wide variety emerging applications including next-generation remote sensing smart mobility high-precision processing manufacturing. Photonic-crystal surface-emitting (PCSELs) show promise to meet these...
We report a (51)V-NMR study on high-quality powder sample of volborthite Cu3V2O7(OH)2 . 2H2O, spin-1/2 Heisenberg antiferromagnet distorted kagome lattice formed by isosceles triangles. In the magnetic fields below 4.5 T, sharp peak in nuclear spin-lattice relaxation rate 1/T(1) accompanied with line broadening revealed transition near 1 K. The low temperature phase shows anomalies such as Lorentzian shape, proportional, variantT behavior indicating dense low-energy excitations, and large...
We have synthesized high-quality single crystals of volborthite, a seemingly distorted kagome antiferromagnet, and carried out high-field magnetization measurements up to 74 T ^{51}V NMR 30 T. An extremely wide 1/3 plateau appears above 28 continues over at 1.4 K, which has not been observed in previous studies using polycrystalline samples. spectra reveal an incommensurate order (most likely spin-density wave order) below 22 simple spin structure the phase. Moreover, novel intermediate...
Abstract Mechanical-free, high-power, high-beam-quality two-dimensional (2D) beam scanning lasers are in high demand for various applications including sensing systems smart mobility, object recognition systems, and adaptive illuminations. Here, we propose demonstrate the concept of dually modulated photonic crystals to realize such lasers, wherein positions sizes photonic-crystal lattice points simultaneously. We show using nano-antenna theory that this nanostructure is essential 2D with...
The effect of gate oxidation temperature on radiation-induced flatband and threshold voltage shifts interface state buildup for steady-state Co60 irradiation have been studied poly-Si MOS capacitors with pyrogenic dry oxides. smallest can be achieved a oxide grown at 850°C. Total dose effects, applied bias during the thickness dependence were also evaluated low capacitors. We obtained 2/3 power law states total thickness.
We demonstrate high-power continuous-wave (CW) lasing oscillation of 1.3-µm wavelength InP-based photonic-crystal surface-emitting lasers (PCSELs). Single-mode operation with an output power over 100 mW, a side-mode suppression ratio (SMSR) 50 dB, and narrow single-lobe beam divergence angle below 1.2° are successfully achieved by using double-lattice photonic crystal structure consisting high-aspect-ratio deep air holes. The double lattice is designed to enhance both the in-plane optical...
Photonic-crystal surface-emitting lasers (PCSELs) are capable of single-mode, high-power lasing over a large resonator area owing to two-dimensional resonance at singularity point the photonic band structure. Since number photons in mode PCSELs much larger than those conventional semiconductor lasers, principle suitable for coherent operation with narrow spectral linewidth. In this paper, we numerically and experimentally investigate intrinsic linewidths 1-mm-diameter under continuous-wave...
We develop a time-dependent three-dimensional coupled-wave theory (3D-CWT) for the transient analysis of photonic-crystal surface-emitting lasers (PCSELs). Our model takes into account temporal evolution both photon and carrier distribution inside PCSELs, which enable various above-threshold lasing characteristics including relaxation oscillation, spatial hole burning, multimode lasing. With developed 3D-CWT, we perform high-power, high-beam-quality PCSELs with double-lattice photonic...
We demonstrate high-output-power and high-efficiency operation of 1.3-µm-wavelength InP-based photonic-crystal surface-emitting lasers (PCSELs). By introducing a metal reflector adjusting the phase reflected light via optimization thickness p-InP cladding layer, we successfully achieve an output power approximately 400 mW with slope efficiency 0.4 W/A wall-plug 20% under CW conditions. In addition, this PCSEL exhibits narrow circular beam divergence angle below 1.6° even at high powers...
<div class="section abstract"><div class="htmlview paragraph">Off-road vehicle demand is on the rise, particularly in North America. In connection with this trend, there a for dynamic modeling to describe behavior of off-road vehicles when driving terrains surfaces successive bumps. However, conventional models has been insufficient representing situation where tire-ground contact and detachment states switch successively during whoops behavior. Therefore, study, rigid-body...
Photonic-crystal surface-emitting lasers (PCSELs) use the two-dimensional (2D) resonance at band-edge of a photonic crystal for lasing, and they feature various outstanding functionalities such as high-brightness arbitrary shaping beam patterns on-chip 2D steering. In this paper, to investigate applicability PCSELs high-speed operation, we design with enhanced in-plane optical feedback, which enable single-mode lasing inside circular region diameter is less than 10 µm. To realize strong...
Abstract 1550 nm wavelength photonic-crystal surface-emitting lasers (PCSELs) are attractive for optical communication and eye-safe sensing applications. In this study, we present InP-based PCSELs featuring a double-lattice structure designed high-power single-mode operation at of nm. These demonstrate output powers exceeding 300 mW under continuous-wave conditions 25 °C. Additionally, highly stable oscillation with side-mode suppression ratio over 60 dB is verified temperatures from 15 °C...
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTAllenylcyclobutanol, a Versatile Initiator for the Palladium-Catalyzed Cascade Reaction: A Novel Route to Bicyclo[5.3.0] and -[6.3.0] FrameworksHideo Nemoto, Masahiro Yoshida, Keiichiro FukumotoView Author Information Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-77, JapanCite this: J. Org. Chem. 1997, 62, 19, 6450–6451Publication Date (Web):September 1997Publication History Received7 July 1997Published online19 September...