A5005227194- Advanced Fiber Laser Technologies
- Orbital Angular Momentum in Optics
- Luminescence and Fluorescent Materials
- Advanced Fiber Optic Sensors
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Laser-Matter Interactions and Applications
- Luminescence Properties of Advanced Materials
- Photonic and Optical Devices
- Diamond and Carbon-based Materials Research
- Solid State Laser Technologies
- Organic Light-Emitting Diodes Research
- Optical Coherence Tomography Applications
- Photorefractive and Nonlinear Optics
- Photonic Crystal and Fiber Optics
- Optical Systems and Laser Technology
- Nanoplatforms for cancer theranostics
- Radiation Detection and Scintillator Technologies
- Semiconductor Quantum Structures and Devices
- Advanced Optical Imaging Technologies
- Laser Material Processing Techniques
- Terahertz technology and applications
- Force Microscopy Techniques and Applications
- Mechanical and Optical Resonators
- Porphyrin and Phthalocyanine Chemistry
University of Tsukuba
2021-2023
National Institute of Advanced Industrial Science and Technology
2017-2020
Ikeda Municipal Hospital
2020
Yamagata University
2019
Chiba University
2015-2016
Herein, triplet-triplet annihilation upconversion (TTA-UC) from near-infrared (NIR, 785 nm) to visible (yellow, centered at 570 regions has been demonstrated in the binary solid of condensed chromophores. Microparticles comprising rubrene as a matrix (emitter) and π-extended Pd-porphyrin dopant (sensitizer) mole ratio 1000:1 were obtained by solution casting. Excitation intensity dependence quantum yield (QY) upconverted emission characterized for individual particles under microscope...
Breaking inversion symmetry in solids plays a central role nonlinear optics because it can change material properties, such as producing even-order optical (NLO) effects. Although centrosymmetric diamond has been developed photonic platform, including waveguides and light sources, the NLO effects bulk diamonds are limited to third-order. Thus, exploiting more powerful second-order effects, second harmonic generation (SHG), still challenging. Here we explore symmetry-breaking-induced using...
We demonstrated a widely tunable 1-μm optical vortex laser formed from 0.532-μm pumpedoptical parametric oscillator with singly-resonant cavity configuration employing cascaded non-critical phase-matching LiB₃O₅ crystals. With this system, the topological charge of pump beam can be selectively transferred to signal or idler output, and output in wavelength range 850-990 nmor 1130-1300 nm could obtained.A maximum energy 0.9 mJ was achieved, corresponding an efficiency 10%.
We developed an octave-band tunable optical vortex laser based on a 532 nm pumped parametric oscillator with simple linear-cavity configuration by employing cascaded non-critical phase-matching LiB3O5 crystals. The output was from 735 to 1903 nm. For pump energy of 9 mJ, pulse 0.24-2.36 mJ obtained, corresponding optical-optical efficiency 0.3-26%.
Peropyrene is a promising candidate molecule for use in organic solar cells based on singlet fission, because it fulfills the energy matching requirement fission. We prepare three 2,9-disubstitued peropyrene derivatives and investigate their crystal structures, photophysical properties, fission phenomenon. Although each derivative shows different molecular overlap motifs solid state, no occurs under normal exciton density conditions due to substantial stabilization of first excited (S 1 )...
Under infrared ultrashort pulse laser stimulation, we investigate temperature-dependent second-harmonic generation (SHG) from nitrogen-vacancy (NV)-introduced bulk diamond. The SHG intensity decreases in the temperature range of 20-300°C, due to phase mismatching caused by refractive index modification. We discover that optical phonon scattering outperforms acoustic NV diamond fitting dependence using a model based on bandgap change via deformation potential interaction. This study presents...
We report the triplet-triplet annihilation (TTA) upconversion (UC) through triplet energy transfer (TET) from a sensitiser fixed on solid surface to free emitters dissolved in solution. A carboxylic-acid derivative of Pt-porphyrin was used as an amino-treated continuous nanoporous glass without aggregation. UC emission observed under photoexcitation 532 nm for porphyrin-fixed immersed emitter solution 9,10-diphenylanthracene (DPA), showing that TET occurs solid-liquid interface. The dynamics...
The room-temperature phosphorescence chromophore, Pt(ii) coproporphyrin I (PtCP), was fixed on the surface of a 3D-network nanoscale pores porous glass through ion-exchange reaction. absorption and spectra indicated that PtCP can be loaded while maintaining monomeric dispersion at concentrations well beyond solubility limits in solution. quantum yield also found to have double enhancement extended lifetime bonded compared solution clearly suppression nonradiative deactivation plays key role...
We report on a direct generation of efficient and wavelength-tunable third-harmonic (THG) from ultrapure electronic-grade (EG) diamond crystals. Under an ultrafast infrared excitation at 1280 nm, the considerably high optical conversion efficiency ~ 0.7% THG wavelength 427 nm is obtained, signal can be tuned over ultra-broadband range 420 to 730 nm. argue that originating minimum absorption loss phase-matching conditions in EG diamond. Enhanced crystal represents new paradigm for...
Epitaxial low temperature grown GaAs (LT-GaAs) on silicon (LT-GaAs/Si) has the potential for terahertz (THz) photoconductive antenna applications. However, crystalline, optical and electrical properties of heteroepitaxial LT-GaAs/Si can be very different from those semi-insulating substrates (reference). In this study, we investigate an epitaxial sample, compared to a reference under same substrate temperature, with layer thickness. Anti-phase domains some crystal misorientation are present...
We developed a widely tunable 1-μm optical vortex laser formed of 0.5-μm pumped parametric oscillator by employing non-critical phase-matching LiB3O5 crystals. Tunable output was obtained in the wavelength range 880–1345nm.
We developed an octave-band tunable optical vortex laser based on a 0.532-μm vortex-pumped parametric oscillator with extended cavity configuration by employing cascaded non-critical phase-matching LiB3O5 crystals. The output was tuned within wavelength range of 735nm-1893nm, and pulse energy 0.24-2.36 mJ also achieved.
In this work, we systematically investigated the ultrafast optical properties of aluminum (Al) thin films on silicon cantilevers using a microscopic femtosecond pump-probe technique to explore effect light irradiation upon while considering radiation pressure and photothermal effects. The laser pulses used for study were less than 30 fs in pulse duration 830 nm wavelength, photon energy (1.49 eV) is close interband transition threshold (ITT) Al. Therefore, change ITT due strain induced by...
This study investigates the ultrafast dynamics of coherent phonons and phonon-polaritons in lithium niobate (LiNbO$_{3}$) crystals using reflective pump-probe spectroscopy with 25-fs time resolution. In addition to several optical phonon modes, electro-optic sampling measurements explored coexistence phonon-polariton E-modes near 3.8 14.9 THz, which agrees considerably theoretical dispersion curves. We also discovered that a lag ($\Delta$t $\approx$ 0.2 ps) between originates from coupling...
Ultrafast dynamics of low-frequency phonon polariton A -mode, longitudinal-optic (LO) modes, transverse-optic (TO) and low high-frequency E -modes in x -cut lithium niobate crystal have been studied using reflection-type pump-probe spectroscopy with an electro-optic sampling technique.
Centrosymmetric crystalline solids, such as diamond, have been developed fundamental photonic platforms like waveguide [1] , and light sources [2] based on nonlinear optical (NLO) effects. Owing to the inversion symmetry of cubic crystal lattice, however, NLO effects in diamond are limited third-order. Thus, studies more powerful useful second-order effects, second harmonic generation (SHG) is still challenging. In this presentation, we report first SHG output from a bulk with help color...