A5082150027- Advanced Fiber Laser Technologies
- Laser-Matter Interactions and Applications
- Solid State Laser Technologies
- Laser Material Processing Techniques
- Photonic Crystal and Fiber Optics
- Laser Design and Applications
- Laser-induced spectroscopy and plasma
- Ocular and Laser Science Research
- Photonic and Optical Devices
- Spectroscopy and Laser Applications
- Photorefractive and Nonlinear Optics
- Advanced Fiber Optic Sensors
- Laser-Plasma Interactions and Diagnostics
- Advanced Surface Polishing Techniques
- Mass Spectrometry Techniques and Applications
- Semiconductor Lasers and Optical Devices
- Advanced Frequency and Time Standards
- Mechanical and Optical Resonators
- Optical Systems and Laser Technology
- Diamond and Carbon-based Materials Research
- Cold Atom Physics and Bose-Einstein Condensates
- Wind Energy Research and Development
- Music Technology and Sound Studies
- Topological Materials and Phenomena
- Surface Roughness and Optical Measurements
The University of Tokyo
2016-2025
Sumitomo Dainippon Pharma (Japan)
2023-2025
Osaka Red Cross Hospital
2018-2024
National Institute of Technology, Maizuru College
2013-2024
Japan Ecology Foundation
2024
National Institute of Advanced Industrial Science and Technology
2005-2022
Institute for Solid State Physics and Optics
2020-2022
International Summer School of Photography
2016-2021
Seoul National University
2021
Institute for Basic Science
2021
We demonstrated single-shot measurements of spectral interference between a white-light continuum generated in hollow-fiber and its second harmonic. The has information on the carrier-envelope phase an input pulse to fiber time delay blue wing continuum. By analyzing observed interference, we estimated shot-by-shot changes phase. This method is useful for determining low-repetition-rate, high-intensity laser.
Two-color phase control in the total ion yield of ionization is successfully demonstrated a tunneling regime by using 100-fs Ti:sapphire laser and its third harmonic. Adding harmonic with an intensity only 10% enhances factor 7. In photoelectron spectra, above threshold peaks due to disappear when two colors are superimposed, resulting continuum spectrum. This shows two-color interference clearly. The intensities high-order harmonics plateau region enhanced order magnitude.
Fourier-transform spectroscopy is an indispensable tool for analyzing chemical samples in scientific research as well the and pharmaceutical industries. Recently, its measurement speed, sensitivity, precision have been shown to be significantly enhanced by using dual-frequency combs. Moreover, recent demonstrations of inducing nonlinear effects with ultrashort pulses enriched utility dual-comb spectroscopy. However, wide acceptance this technique hindered requirement two frequency combs...
Toll-like receptor 4 (TLR4) is an indispensable immune for lipopolysaccharide (LPS), a major component of the Gram-negative bacterial cell wall. Following LPS stimulation, TLR4 transmits signal from surface and becomes internalized in endosome. However, spatial regulation signaling not fully understood. Here, we investigated mechanisms LPS-induced internalization clarified roles extracellular LPS-binding molecules, protein (LBP), glycerophosphatidylinositol-anchored (CD14). stimulation...
We describe a Yb-fiber-based laser comb, with focus on the relationship between net-cavity dispersion and frequency noise comb. While tuning from anomalous to normal, we measure relative intensity noise, offset (f(CEO)) linewidth, resulting spectrum f(CEO). find that operating at zero has many advantages, including an approximately 100× reduction in free-running f(CEO) linewidth power spectral density when compared normal-dispersion regime. At zero-dispersion point, demonstrate phase-locked...
Background:Venous thromboembolism (VTE) has a long-term risk of recurrence, which can be prevented by anticoagulation therapy.
Autocorrelation measurement was demonstrated for the first time to our knowledge in XUV region measure width of a high-order harmonic pulse. Two-photon ionization rare gases used as nonlinear process autocorrelation measurement. The 27-fs pulse that obtained is, knowledge, shortest region.
An ultrashort-pulse, mode-locked ytterbium-doped fiber laser has been developed. The group-delay dispersion was compensated with a grating pair inside the cavity. A broad spectrum from 1000-nm to 1120-nm obtained without intracavity compensation of third-order dispersion. 0.7-nJ pulse as short 28.3 fs repetition rate 80 MHz. To our knowledge, this is shortest reported an Yb oscillator.
We demonstrate a fiber Bragg grating (FBG) strain sensor with optical frequency combs. To precisely characterize the response of FBG when is applied, dual-comb spectroscopy used. Highly sensitive enabled measurements resolution 34 nε. The spectral bandwidth measurement exceeds 1 THz. Compared conventional using continuous-wave laser that requires rather slow scanning limited range, dynamic range and multiplexing capability are significantly improved by broadband spectroscopy.
We report on the development of an optical parametric chirpedpulse amplifier at a 1-kHz repetition rate with 5.5-fs pulse duration, 2.7-mJ energy and carrier-envelope phase-control. The is pumped by 450-nm from frequency-doubled Ti:sapphire laser.
A 15-GHz mode spacing optical frequency comb based on a Kerr-lens mode-locked Yb:Y2O3 ceramic laser has been developed. Individual modes were clearly resolved by commercial spectrometer. To demonstrate the long-term operation of comb, single longitudinal was phase-locked to frequency-stabilized continuous wave and repetition rate radio standard. best our knowledge, 15 GHz is largest reported (repetition rate) for both direct femtosecond based-optical comb.
Intracavity high harmonic generation was utilized to generate average-power coherent radiation at vacuum ultraviolet (vuv) wavelengths. A ytterbium-doped fiber-laser based master-oscillator power-amplifier (MOPA) system with a 10 MHz repetition frequency developed and used as driving laser for an external cavity. series of odd-order radiations generated extending down ∼ 30 nm (41 eV in photon energy). The 7th centered 149 had average output power up 0.5 mW. In this way, we sub-mW vuv-laser...
We present a compact, Kerr-lens mode-locked oscillator consisting of three-element optical setup and demonstrate femtosecond pulse generation at repetition rate 23.8 GHz.
Recent developments of transition-edge sensors (TESs), based on extensive experience in ground-based experiments, have been making the sensor techniques mature enough for their application future satellite CMB polarization experiments. LiteBIRD is most advanced phase among such satellites, targeting its launch Japanese Fiscal Year 2027 (2027FY) with JAXA's H3 rocket. It will accommodate more than 4000 TESs focal planes reflective low-frequency and refractive medium-and-high-frequency...
Abstract Ultrashort pulse laser drilling is a promising method for the fabrication of microchannels in dielectric materials. Due to complexity process, there strong demand numerical models (simulators) that can predict structures produced under specific processing conditions order rapidly find optimal parameters. However, validity conventional simulators dielectrics has been confined range strict interpolations data used during construction model, and thus, their usefulness limited. Here, we...
We demonstrate cascaded nonlinear pulse compression of a Yb-doped fiber laser. The system is based on two stages with bare single-mode (SMF) and ultra-high NA (UHNA) fibers combined pairs chirped mirrors. 10 nJ, 110 fs input pulses are compressed down to 9.1 at 90 MHz, revealing broadband spectrum from 800 nm 1350 nm. This technique provides simple approach sub-10-fs compact lasers for variety applications.
FLASH has been shown to be required for S phase progression and interact with a nuclear protein, ataxia-telangiectasia locus (NPAT), component of Cajal bodies in the nucleus an activator histone transcription. We investigated role human by using inducible knockdown system presence or absence various mutant forms mouse FLASH. While carboxyl-terminal deletion mutants FLASH, which do not NPAT, can support progression, its amino-terminal mutants, are unable self associate, cannot...
The paper describes a time- and angle-resolved photoemission apparatus consisting of hemispherical analyzer pulsed laser source. We demonstrate 1.48-eV pump 5.92-eV probe measurements at the ⩾10.5-meV ⩾240-fs resolutions by use fairly monochromatic 170-fs pulses delivered from regeneratively amplified Ti:sapphire system operating typically 250 kHz. is capable to resolve optically filled superconducting peak in unoccupied states cuprate superconductor, Bi2Sr2CaCu2O(8 + δ). A dataset recorded...
Abstract A 100 W Yb-doped, fiber-based, femtosecond, chirped pulse amplification laser system was developed with a repetition rate of 1 MHz, corresponding to energy µJ. Large-scale, fused-silica transmission gratings were used for both the stretcher and compressor, compression throughput efficiency ∼85%. duration 270 fs measured by second harmonic generation frequency-resolved optical gating (SHG-FROG). To best our knowledge, this is shortest ever achieved 100-W-level fiber at few megahertz,...
At present, deep ultraviolet (DUV) lasers at the wavelength of fourth harmonics 1 μm (266 nm/258 nm) and 193 nm are widely utilized in science industry. We review generation these DUV by nonlinear frequency conversion processes using solid-state/fiber as fundamental frequency. A laser 258 (FHG) could achieve an average power 10 W with a beam quality M2 < 1.5. Moreover, was obtained sum-frequency (SFG). new concept 193-nm use diamond Raman is also introduced. proof-of-principle experiment...
Laser-based material removal, or ablation, using ultrafast pulses enables precision micro-scale processing of almost any for a wide range applications and is likely to play pivotal role in providing mass customization capabilities future manufacturing. However, optimization the parameters can currently take several weeks because absence an appropriate simulator. The difficulties realizing such simulator lie multi-scale nature relevant processes high nonlinearity irreversibility these...
We experimentally elucidate the origin of anomalous Hall conductivity in a three-dimensional Dirac semimetal, ${\mathrm{Cd}}_{3}{\mathrm{As}}_{2}$, driven by circularly polarized light. Using time-resolved terahertz Faraday rotation spectroscopy, we determine transient spectrum with special attention to its sign. Our results clearly show dominance direct photocurrent generation assisted electric field. The contribution from Floquet-Weyl nodes is found be minor when driving light resonance...
Abstract Background Rho-kinase is a serine/threonine kinase and regulates actin dynamics. There are two subtypes: 1 2. Recently, we found that Rho-kinase1/2 inhibitor, fasudil, ameliorated schizophrenia-like behaviors in MK-801-treated mice (Takase et al., 2022). However, fasudil has been shown side effects, such as hypotension, which may hinder its clinical application for schizophrenia. Since 2 predominantly expressed brain, hypothesized selective inhibition of might exhibit...