Temperature and Vibration Dependence of the Faraday Effect of Gd₂O₃ NPs-Doped Alumino-Silicate Glass Optical Fiber.

All-optical fiber magnetic field sensor based on the Gd₂O₃ nano-particles (NPs)-doped alumino-silicate glass optical fiber was developed, and its temperature and vibration dependence on the Faraday Effect were investigated. Uniformly embedded Gd₂O₃ NPs were identified to form in the core of the fiber, and the measured absorption peaks of the fiber appearing at 377 nm, 443 nm, and 551 nm were attributed to the Gd₂O₃ NPs incorporated in the fiber core. The Faraday rotation angle (FRA) of the linearly polarized light was measured at 650 nm with the induced magnetic field by the solenoid.

Amplification by white light-emitting diode pumping of large-core Er-doped fiber with 12 dB gain.

We have developed a cost-effective, high-capacity Er-doped fiber amplifier based on the high-power white LED and a large-core Er-doped fiber. Er ions of the fiber with absorption bands at 453, 488, 523, and 654 nm were simultaneously excited by LED pumping and amplification with optical gain over 12 dB at 1550 nm was obtained.

Effect of Zn addition on non-resonant third-order optical nonlinearity of the Cu-doped germano-silicate optical glass fiber.

Cu/Zn-codoped germano-silicate optical glass fiber was manufactured by using the modified chemical vapor deposition (MCVD) process and solution doping process. To investigate the reduction effect of Zn addition on Cu metal formation in the core of the Cu/Zn-codoped germano-silicate optical glass fiber, the optical absorption property and the non-resonant third-order optical nonlinearity were measured. Absorption peaks at 435 nm and 469 nm in the Cu/Zn-codoped germano-silicate optical glass fiber were contributed to Cu metal particles and ZnO semiconductor particles, respectively.

Effective supercontinuum generation by using highly nonlinear dispersion-shifted fiber incorporated with Si nanocrystals.

The dispersion-shifted fiber (DSF) incorporated with Si nanocrystals (Si-NCs) having highly nonlinear optical property was fabricated to investigate the effective supercontinuum generation characteristics by using the MCVD process and the drawing process. Optical nonlinearity was enhanced by incorporating Si nanocrystals in the core of the fiber and the refractive index profile of a dispersion-shifted fiber was employed to match its zero-dispersion wavelength to that of the commercially available pumping source for generating effective supercontinuum. The non-resonant nonlinear refractive index, n2, of the Si-NCs doped DSF measured by the cw-SPM method was measured to be 7.

Fabrication of highly nonlinear germano-silicate glass optical fiber incorporated with PbTe semiconductor quantum dots using atomization doping process and its optical nonlinearity.

Germano-silicate glass optical fiber incorporated with PbTe semiconductor quantum dots (SQDs) in the core was fabricated by using the atomization process in modified chemical vapor deposition (MCVD) process. The absorption bands attributed to PbTe semiconductor quantum dots in the fiber core were found to appear at around 687 nm and 1055 nm. The nonlinear refractive index measured by the long-period fiber grating (LPG) pair method upon pumping with laser diode at 976.

Development of a highly sensitive compact sized optical fiber current sensor.

We have experimentally developed a highly sensitive and a compact size current sensor by using the CdSe quantum dots-doped bend insensitive optical fiber, operating in the visible band of wavelength. The modified sensitivity of this sensor was about 675 microrad/(Turn.A.

A simple and reliable method to determine LP(11) cutoff wavelength of bend insensitive fiber.

We present a simple and reliable method based on the spectral splice loss measurement to determine the cutoff wavelength of bend insensitive fiber.

Intense green upconversion emission in Tb3+/Yb3+ codoped alumino-germano-silicate optical fibers.

We observed intense green upconversion emission from Tb(3+) centered at 546 nm due to transition D(4)5-->F(5)7 in Tb(3+)/Yb(3+) codoped alumino-germano-silicate optical fibers by direct excitation of Yb(3+) ions with a laser diode at 976 nm. A two-photon cooperative energy transfer upconversion among a pair of Yb(3+) donor ions and a Tb(3+) acceptor ion are responsible for the observed green emission. Appropriately increasing the concentration of Tb(3+) relative to Yb(3+) was found to facilitate the energy transfer upconversion process from Yb(3+) to Tb(3+), while an excess of Tb(3+) ions inversely introduced more of the concentration quenching effect and phonon-assistant backward energy transfer from Tb(3+) to Yb(3+) and, therefore, damaged the observed green emission.

Bend insensitive optical fiber with ultralow bending loss in the visible wavelength band.

We report experimental development of a single-mode optical fiber optimized for a wavelength band of 400 nm to 700 nm, which showed negligible bending loss of 0.09 dB/loop at 400 nm and 0.23 dB/loop at 633 nm for a loop diameter of 10 mm.

Near zero bending loss in a double-trenched bend insensitive optical fiber at 1550 nm.

We have developed a new single-mode optical fiber (SMF) which exhibits ultra low bend sensitivity over a wide communication band. The measured mean bending loss at 1550 nm was about 0.0095 dB for a loop of 10 mm diameter.

Tellurium-enhanced nonresonant third-order optical nonlinearity in a germanosilicate optical fiber.

A tellurium-doped germanosilicate optical fiber was developed by modified chemical vapor deposition and solution doping techniques. Using the continuous-wave self-phase modulation method, the nonresonant nonlinear refractive index, n2, was measured to be 5.52 x 10(-20) m2/W, which is 2 to 3 times that of the undoped germanosilicate glass fiber.

Design and development of a trenched optical fiber with ultra-low bending loss.

We have designed and experimentally demonstrated a single mode optical fiber with a very low bending loss of about 0.014 dB/loop at 1550 nm for a bending radius of 5 mm.

All-optical switching application of germano-silicate optical fiber incorporated with Ag nanocrystals.

Ag-nanocrystal-incorporated germano-silicate optical fiber with high resonant nonlinearity was fabricated by using modified chemical vapor deposition and solution doping techniques. An all-optical signal switching application based on cross-phase modulation was demonstrated in the cascaded long-period fiber gratings. Pumped with 499 nm argon laser, all-optical signal gating of the pi-phase shift was achieved with low pump intensities of less than 7.

Enhanced current sensitivity in the optical fiber doped with CdSe quantum dots.

A new optical fiber current sensor using a CdSe quantum dots doped optical fiber has been demonstrated with high Faraday rotation for remote sensing of current from 0 to 40 Amperes. It showed enhancement in the current sensitivity by about 2 times than that of the single mode optical fiber current sensor at 632 nm.

Design of a trenched bend insensitive single mode optical fiber using spot size definitions.

We have designed a bend insensitive single mode optical fiber with a low-index trench using spot-size definitions and their optimization technique. The bending loss at a 5 mm of bending radius was negligible, while single mode properties were intact.

Single-mode optical fiber design with wide-band ultra low bending-loss for FTTH application.

We propose a new design of a single-mode optical fiber (SMF) which exhibits ultra low bend sensitivity over a wide communication band (1.3 microm to 1.65 microm).

Fabrication and optical characteristics of a novel optical fiber doped with the Au nanoparticles.

Optical fibers containing gold metal nanoparticles were developed by modified chemical vapor deposition, in which Au(OH)3 and tetraethyl-orthosilicate (TEOS) was used via sol-gel process to incorporate gold metals by providing the reduction atmosphere. The absorption peak appeared near 490 nm was found to be due to the surface plasmon resonance of the gold nanoparticles incorporated in the fiber core.