A5057935941- Optical Network Technologies
- Advanced Photonic Communication Systems
- Photonic Crystal and Fiber Optics
- Advanced Fiber Optic Sensors
- Advanced Optical Network Technologies
- Semiconductor Lasers and Optical Devices
- Advanced Fiber Laser Technologies
- Photonic and Optical Devices
- Optical Coherence Tomography Applications
- Myasthenia Gravis and Thymoma
- Photoacoustic and Ultrasonic Imaging
- Central Venous Catheters and Hemodialysis
- Power Line Communications and Noise
- Venous Thromboembolism Diagnosis and Management
- Coronary Interventions and Diagnostics
- Congenital Heart Disease Studies
- Advanced Wireless Communication Techniques
- Shoulder and Clavicle Injuries
- Vascular anomalies and interventions
- Neuroendocrine Tumor Research Advances
- Cardiac tumors and thrombi
- Cardiac Valve Diseases and Treatments
- Coronary Artery Anomalies
- Solid State Laser Technologies
- Advanced Fluorescence Microscopy Techniques
Sumitomo Electric Industries (Japan)
2016-2025
Sumitomo Electric Industries (United States)
2006-2018
Photonics Electronics Technology Research Association
2004
Hokkaido University
2003
The University of Tokyo
1999
Jichi Medical University
1989
In order to control dispersion and slope of indexguiding photonic crystal fibers (PCFs), a new controlling technique chromatic in PCF is reported. Moreover, our applied design with both ultra-low ultra-flattened wide wavelength range. A full-vector finite element method anisotropic perfectly matched layers used analyze the properties confinement losses number air holes. It shown from numerical results that it possible fourring flattened 0 +/- 0.5 ps/(km.nm) 1.19 m 1.69 range five-ring 0.4 1.23 1.72
We achieved the lowest-ever transmission losses of 0.1419 dB/km at 1560 nm wavelength and 0.1424 1550 in a Ge-free silica-core optical fiber. It was an improvement by 4 mdB/km from previous record realized 2015. The silica core included fluorine co-doping, which helps to reduce disorder microscopic glass network structure that causes Rayleigh scattering loss without significant increase waveguide imperfection loss. A two-layered polymer coating with inner layer having lower elastic modulus...
Newly developed 125-μm-cladding coupled four-core fibers realized the record-low spatial mode dispersion (SMD) of 3.14 ± 0.17 ps/√km over C-band and ultra-low attenuation 0.158 dB/km at 1550 nm, both which are lowest ever reported among optical for space-division multiplexed transmission. The SMD was observed to be proportional fiber bend curvature, i.e., inversely radius, measured bending radius ~31 cm. By assuming 3.14-ps/√km accumulation, tap count multiple-input multiple-output digital...
Randomly-coupled multi-core fiber (MCF) technology has come to attract lots of attention because its strong applicability long-haul transmission systems. Compared with weakly-coupled MCFs independent cores, it can simultaneously realize higher spatial channel density and ultralow loss using existing ultralow-loss single-mode (SMF) core designs. The mode coupling characteristics randomly-coupled provide favorable optical properties, such as suppressed accumulation modal dispersion (MD),...
We show combined SDM/WDM transmission over a novel 7-core coupled-core fiber distances up to 12100 km for QPSK and 4400 16QAM signals, with corresponding spectral efficiency of 21 bit/s/Hz 42 bit/s/Hz. The measurements that such clearly outperforms an equivalent single-mode resulting in more than 7 times the capacity.
We have developed a spectroscopic optical coherence tomography (OCT) for imaging lipid distribution within blood vessel in order to detect coronary artery plaque. A 1.7-μm spectral-domain OCT with A-scan rate of 47 kHz is fabricated using broadband light source based on super-luminescent diodes and spectrometers extended InGaAs line sensors. demonstrate an vitro model lipid. The sensitivity specificity the differentiation between are 87% 90% training, respectively. validation test also shows...
Coupled-core multicore fibers provide significant advantages for long-haul high capacity fiber optics communication: Cores with large effective areas can be densely packed, and show a better tolerance to nonlinear effects compared single-mode equivalent cores.
We review and discuss the design factors considerations on MCFs for bidirectional transmissions, including connection polarity crosstalk requirements. also introduce suitable long-haul short-reach transmissions.
Hole-assisted lightguide fiber (HALF) is a microstructured comprising material index profile for waveguiding and air holes modifying optical properties. Anomalous dispersion larger than those of the conventional fibers can be realized without severe degradation in loss, because low power fraction structural simplicity. We investigate into causes loss fabricated HALFs, show that GeO2-doped core, addition to fraction, desirable loss. The HALF exhibits as 0.41 dB/km large anomalous +35 ps/nm/km...
A 125-µm-cladding coupled four-core fiber realized 0.158-dB/km attenuation at 1550 nm and 6.1-ps/km1/2 spatial mode dispersion over C-band, both of which are the lowest ever reported among optical fibers for space-division multiplexed transmission.
Fiber figure of merit (FOM), derived from the GN-model theory and validated by several experiments, can predict improvement in OSNR or transmission distance using advanced fibers. We review FOM present design results optimal fiber for large capacity long haul transmission, showing variation according to system configuration.
We report on the design, fabrication, and experimental characterization of germanium-doped graded-index multi-mode fibers that are tailored to achieve broadband operation for inter-modal Bragg scattering four wave mixing process. First, we show increasing core diameter decreases separation between pumps signal/idler pair. Second, demonstrate a conversion efficiency bandwidth (7 nm) more than twice achieved previously with half fiber length (50 m).
We demonstrate a 4-core fiber amplifier that has strongly coupled cores at both the pump and signal wavelengths. Strong mode-coupling minimizes mode dependent loss simplifies requirements on spatial uniformity of pump.
We realized 125-μm-cladding 2-core fiber with 0.162-dB/km attenuation, lowest-ever among uncoupled multi-core fibers, and effective areas of 112μm2. It can enable 1.34-times higher capacity without increasing power consumption, compared a state-of-the-art submarine single-mode fiber.
Intermodal four-wave mixing can be exploited to perform nonlinear signal processing functionalities, such as all-optical wavelength conversion. Those functions used e.g. for switching applications in conventional single-mode fiber transmission systems. In this paper, we report on a sub-system convert signals from various wavelengths the C-band L-band with conversion bandwidth of more than 40 nm. The is based newly designed highly few-mode specially engineered dispersion characteristics...
We propose a novel holed fiber based on lightguiding by glass index difference and dispersion enhancement holes. Due to the reduced power fraction in holes, record-breaking low loss of 0.82 dB/km at 1550 nm is achieved with extraordinarily large anomalous +34 ps/nm/km.
A new technique for reducing timing jitter by using a cascaded second-order nonlinear process in quasi-phase-matched (QPM) LiNbO3 waveguides is proposed. It was found that the of signal at QPM wavelength not transferred to converted pulses during cascading 30-mm-long waveguide. Timing-jitter transfer characteristics are evaluated calculation pulse evolution, and retiming 1.5-ps 10- demonstrated experimentally.
We demonstrate a mode-locked Er:fiber laser with compact fiber-pigtailed optical bench containing free-space electro-optic modulator for high-speed feedback control. The achieved servo bandwidth of the beat frequency between given comb component and reference is approximately 850 kHz. realization narrow-linewidth highly stable confirmed by measuring both in-loop out-of-loop frequencies. also measurement two iodine-stabilized Nd:YAG lasers through without stability degradation. developed can...
We experimentally demonstrate a means to selectively enhance wavelength conversion of WDM channels on 100 GHz grid exploiting nonlinear effects between the spatial modes few mode fiber. The selectivity parametric gain is obtained by dispersion design fiber such that inverse group velocity curves participating are parallel and their suitably large. describe both theoretically observed dependence idler profile pump (quasi) degeneracy.