Takenobu Suzuki

Bio: Takenobu Suzuki is an academic researcher from Toyota Technological Institute. The author has contributed to research in topics: Optical fiber & Photonic-crystal fiber. The author has an hindex of 37, co-authored 504 publications receiving 5361 citations. Previous affiliations of Takenobu Suzuki include Toyota.

Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber

Abstract: Ultrabroadband supercontinuum light expanding from ultraviolet to 6.28 μm is generated in a centimeter-long fluoride fiber pumped by a 1450 nm femtosecond laser. The spectral broadening in the fluoride fiber is caused by self-phase modulation, Raman scattering and four-wave mixing. The experimental and simulated results show that fluoride fiber is a promising candidate for generating the midinfrared supercontinuum light up to 8 μm.

Mid-infrared supercontinuum generation spanning 2.0 to 15.1 μm in a chalcogenide step-index fiber.

Abstract: We experimentally demonstrate mid-infrared (MIR) supercontinuum (SC) generation spanning ∼2.0 to 15.1 μm in a 3 cm-long chalcogenide step-index fiber. The pump source is generated by the difference frequency generation with a pulse width of ∼170 fs, a repetition rate of ∼1000 Hz, and a wavelength range tunable from 2.4 to 11 μm. To the best of our knowledge, this is the broadest MIR SC generation observed so far in optical fibers. It facilitates fiber-based applications in sensing, medical, and biological imaging areas.

Microstructured chalcogenide optical fibers from As(2)S(3) glass: towards new IR broadband sources.

Abstract: The aim of this paper is to present an overview of the recent achievements of our group in the fabrication and optical characterizations of As2S3 microstructured optical fibers (MOFs). Firstly, we study the synthesis of high purity arsenic sulfide glasses. Then we describe the use of a versatile process using mechanical drilling for the preparation of preforms and then the drawing of MOFs including suspended core fibers. Low losses MOFs are obtained by this way, with background level of losses reaching less than 0.5 dB/m. Optical characterizations of these fibers are then reported, especially dispersion measurements. The feasibility of all-optical regeneration based on a Mamyshev regenerator is investigated, and the generation of a broadband spectrum between 1 µm and 2.6 µm by femto second pumping around 1.5 µm is presented.

Tellurite microstructure fibers with small hexagonal core for supercontinuum generation.

Abstract: Tellurite glass microstructure fibers with a 1 µm hexagonal core were fabricated successfully by accurately controlling the temperature field in the fiber-drawing process The diameter ratio of holey region to core (DRHC) for the fiber can be adjusted freely in the range of 1–20 by pumping a positive pressure into the holes when drawing fiber, which provides much freedom in engineering the chromatic dispersion With the increase of DRHC from 35 to 20, the zero dispersion wavelengths were shifted several hundred nanometers, the cutoff wavelength due to confinement loss was increased from 1600 nm to 3800 nm, and the nonlinear coefficient γ was increased from 39 to 57 W-1/m Efficient visible emissions due to third harmonic generation were found for fibers with a DRHC of 10 and 20 under the 1557 nm pump of a femtosecond fiber laser One octave flattened supercontinuum spectrum was generated from fibers with a DRHC of 35, 10 and 20 by the 1064 nm pump of a picosecond fiber laser To the best of our knowledge, we have for the first time fabricated a hexagonal core fiber by soft glass with such a small core size, and have demonstrated a large influence of the holey region on the dispersion, nonlinear coefficient and supercontinuum generation for such fiber

Mid-infrared supercontinuum generation in a suspended-core As2S3 chalcogenide microstructured optical fiber.

Abstract: We demonstrate the supercontinuum (SC) generation in a suspended-core As2S3 chalcogenide microstructured optical fiber (MOF) The variation of SC is investigated by changing the fiber length, pump peak power and pump wavelength In the case of long fibers (20 and 40 cm), the SC ranges are discontinuous and stop at the wavelengths shorter than 3500 nm, due to the absorption of fiber In the case of short fibers (13 and 24 cm), the SC ranges are continuous and can extend to the wavelengths longer than 4 μm The SC broadening is observed when the pump peak power increases from 024 to 132 kW at 2500 nm The SC range increases with the pump wavelength changing from 2200 to 2600 nm, corresponding to the dispersion of As2S3 MOF from the normal to anomalous region The SC generation is simulated by the generalized nonlinear Schrodinger equation The simulation includes the SC difference between 13 and 24 cm long fiber by 2500 nm pumping, the variation of SC with pump peak power in 24 cm long fiber, and the variation of SC with pump wavelength in 13 cm long fiber The simulation agrees well with the experiment

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Mid-infrared frequency combs

Abstract: This Review discusses the emerging field of mid-infrared frequency comb generation, including technologies based on novel laser gain media, nonlinear frequency conversion and microresonators, as well as the applications of these combs in precision spectroscopy and direct frequency comb spectroscopy. Laser frequency combs are coherent light sources that emit a broad spectrum of discrete, evenly spaced narrow lines whose absolute frequency can be measured to within the accuracy of an atomic clock. Their development in the near-infrared and visible domains has revolutionized frequency metrology while also providing numerous unexpected opportunities in other fields such as astronomy and attosecond science. Researchers are now exploring how to extend frequency comb techniques to the mid-infrared spectral region. Versatile mid-infrared frequency comb generators based on novel laser gain media, nonlinear frequency conversion or microresonators promise to significantly expand the applications of frequency combs. In particular, novel approaches to molecular spectroscopy in the 'fingerprint region', with dramatically improved precision, sensitivity, recording time and/or spectral bandwidth may lead to new discoveries in the various fields relevant to molecular science.