Sze Yun Set

Bio: Sze Yun Set is an academic researcher from University of Tokyo. The author has contributed to research in topics: Fiber laser & Laser. The author has an hindex of 29, co-authored 191 publications receiving 3662 citations. Previous affiliations of Sze Yun Set include University of Southampton & Oita University.

Laser mode locking using a saturable absorber incorporating carbon nanotubes

Abstract: This paper describes a new class of saturable absorber device based on single-wall carbon nanotube (SWNT)-the saturable absorber incorporating nano tube (SAINT). The device possesses ultrafast optical properties comparable to that of the industrial standard semiconductor saturable absorber mirror (SESAM). Passively mode-locked picosecond fiber lasers in different configurations are demonstrated using SAINTs as mode lockers. This is the first demonstration of optical pulsed lasers based on the carbon nanotube technology, and the first practical application of carbon nanotubes in the field of applied optics.

Saturable absorbers incorporating carbon nanotubes directly synthesized onto substrates and fibers and their application to mode-locked fiber lasers

Abstract: We present novel carbon-nanotube-based saturable absorbers. Using the low-temperature alcohol catalytic chemical-vapor deposition method, high-quality single-walled carbon nanotubes (SWNTs) were directly synthesized on quartz substrates and fiber ends. We successfully applied the SWNTs to mode lock a fiber laser producing subpicosecond pulses at a 50-MHz repetition rate.

Ultrafast fiber pulsed lasers incorporating carbon nanotubes

Abstract: We present the first passively mode-locked fiber lasers based on a novel saturable absorber incorporating carbon nanotubes (SAINT). This device offers several key advantages such as: ultrafast recovery time (<1 ps), high-optical damage threshold, mechanical and environmental robustness, chemical stability, and the ability to operate in transmission, reflection, and bidirectional modes. Moreover, the fabrication cost and complexity of SAINT devices are potentially lower than that of conventional semiconductor saturable absorber mirror devices. Therefore, it is expected that SAINT will greatly impact future pulsed laser design and development.

Carbon nanotube mode lockers with enhanced nonlinearity via evanescent field interaction in D-shaped fibers.

Abstract: We demonstrate a novel passive mode-locking scheme for pulsed lasers enhanced by the interaction of carbon nanotubes (CNTs) with the evanescent field of propagating light in a D-shaped optical fiber. The scheme features all-fiber operation as well as a long lateral interaction length, which guarantees a strong nonlinear effect from the nanotubes. Mode locking is achieved with less than 30% of the CNTs compared with the amount of nanotubes used for conventional schemes. Our method also ensures the preservation of the original morphology of the individual CNTs. The demonstrated pulsed laser with our CNT mode locker has a repetition rate of 5.88 MHz and a temporal pulse width of 470 fs.

Mode-locked fiber lasers based on a saturable absorber incorporating carbon nanotubes

Abstract: A novel passively mode-locked fiber laser is demonstrated using saturable absorber based on single-walled carbon nanotubes. This is the first demonstration of an optical pulsed laser based on carbon nanotube technology.

Atomic‐Layer Graphene as a Saturable Absorber for Ultrafast Pulsed Lasers

Abstract: The optical conductance of monolayer graphene is defined solely by the fine structure constant, α = (where e is the electron charge, is Dirac's constant and c is the speed of light). The absorbance has been predicted to be independent of frequency. In principle, the interband optical absorption in zero-gap graphene could be saturated readily under strong excitation due to Pauli blocking. Here, use of atomic layer graphene as saturable absorber in a mode-locked fiber laser for the generation of ultrashort soliton pulses (756 fs) at the telecommunication band is demonstrated. The modulation depth can be tuned in a wide range from 66.5% to 6.2% by varying the graphene thickness. These results suggest that ultrathin graphene films are potentially useful as optical elements in fiber lasers. Graphene as a laser mode locker can have many merits such as lower saturation intensity, ultrafast recovery time, tunable modulation depth, and wideband tunability.

Atomic layer graphene as saturable absorber for ultrafast pulsed lasers

Abstract: The optical conductance of monolayer graphene is defined solely by the fine structure constant. The absorbance has been predicted to be independent of frequency. In principle, the interband optical absorption in zero-gap graphene could be saturated readily under strong excitation due to Pauli blocking. Here, we demonstrate the use of atomic layer graphene as saturable absorber in a mode-locked fiber laser for the generation of ultrashort soliton pulses (756 fs) at the telecommunication band. The modulation depth can be tuned in a wide range from 66.5% to 6.2% by varying the thickness of graphene. Our results suggest that ultrathin graphene films are potentially useful as optical elements in fiber lasers. Graphene as a laser mode locker can have many merits such as lower saturation intensity, ultrafast recovery time, tunable modulation depth and wideband tuneability.

Subwavelength-diameter silica wires for low-loss optical waveguiding

Abstract: The present invention provides nanometer-sized diameter silica fibers that exhibit high diameter uniformity and surface smoothness. The silica fibers can have diameters in a range of a about 20 nm to about 1000 nm. An exemplary method according to one embodiment of the invention for generating such fibers utilizes a two-step process in which in an initial step a micrometer sized diameter silica preform fiber is generated, and in a second step, the silica preform is drawn while coupled to a support element to form a nanometer sized diameter silica fiber. The portion of the support element to which the preform is coupled is maintained at a temperature suitable for drawing the nansized fiber, and is preferably controlled to exhibit a temporally stable temperature profile.

The chemistry of graphene

Abstract: A review on the latest developments on graphene, written from the perspective of a chemist, is presented. The role of chemistry in bringing graphene research to the next level is discussed.

Carbon-nanotube photonics and optoelectronics

Abstract: Carbon nanotubes possess unique properties that make them potentially useful in many applications in optoelectronics. This review describes the fundamental optical behaviour of carbon nanotubes as well as their opportunities for light generation and detection, and photovoltaic energy generation.