Development of Germano-Silicate Optical Fiber Incorporated with Germanium Nanoparticles and Its Optical Characteristics.

The germano-silicate optical fiber incorporated with Ge nanoparticles with enhanced optical nonlinearity was developed by using modified chemical vapor deposition and drawing processes. A broad photoluminescence band obtained by pumping with the 404 nm superluminescent diode was found to appear from 540 nm to 1,000 nm. The non-resonant nonlinear refractive index, n2, of the fiber measured by the continuous wave self-phase modulation method was 4.

Surface Plasmon Resonance Characteristics of Optical Fiber Incorporated with Au Nano-Particles in Cladding Region.

A novel surface plasmon resonance (SPR) sensor based on specialty optical fiber having its cladding doped with Au nano-particles (NPs) was developed by modified chemical vapor deposition process. To optimize the SPR absorption and sensitivity of the fiber SPR sensor, effect of the fiber length (20 cm-90 cm) on sensing capability of refractive index (n = 1.418-1.

Gamma-ray radiation response at 1550 nm of fluorine-doped radiation hard single-mode optical fiber.

We have investigated gamma-ray radiation response at 1550 nm of fluorine-doped radiation hard single-mode optical fiber. Radiation-induced attenuation (RIA) of the optical fiber was measured under intermittent gamma-ray irradiations with dose rate of ~10 kGy/h. No radiation hardening effect on the RIA by the gamma-ray pre-dose was found when the exposed fiber was bleached for long periods of time (27~47 days) at room-temperature.

Radial-firing optical fiber tip containing conical-shaped air-pocket for biomedical applications.

We report a novel radial-firing optical fiber tip containing a conical-shaped air-pocket fabricated by deforming a hollow optical fiber using electric arc-discharge process. The hollow optical fiber was fusion spliced with a conventional optical fiber, simultaneously deforming into the intagliated conical-shaped region along the longitudinal fiber-axis of the fiber due to the gradual collapse of the cavity of the hollow optical fiber. Then the distal-end of the hollow optical fiber was sealed by the additional arc-discharge in order to obstruct the inflow of an external bio-substance or liquid to the inner air surface during the surgical operations, resulting in the formation of encased air-pocket in the silica glass fiber.

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.

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.