Search results for "fiber"
showing 10 items of 2343 documents
Influence of parametric four-wave mixing effects on stimulated Raman scattering in bimodal optical fibers.
2007
We analyze stimulated Raman scattering in normally dispersive bimodal fibers under single-frequency pumping conditions. Experiments show that whenever the interacting nonlinear waves propagate in the LP(01) and LP(11) modes, a parametric four-wave mixing enters unavoidably into play in the wave-coupling behavior, which causes qualitatively different phenomena compared with the ordinary process of Raman scattering, such as the parametric suppression of the first-order Raman Stokes radiation.
Mid-infrared supercontinuum generation in suspended-core Chalcogenide and Tellurite optical fibers
2013
We report the experimental generation of mid-infrared supercontinuum in tellurite and chalcogenide suspended-core fibers pumped close to their zero-dispersion in femtosecond regime. The resulting supercontinua extend until 2.8µm in tellurite and 3.2µm in chalcogenide fibers.
Strong reduction of optimum pump power for efficient wave conversion in optical fibers with dual-frequency circularly polarized pump waves.
2002
We present experiments that show achievement of highly efficient generation of parametric sidebands in an optical fiber with dual-frequency, circularly polarized pump waves. An appropriate choice of the separation between the pump frequencies permits a strong reduction of the optimum power for highly efficient frequency conversion.
Broadband Tuning of Polarization Modulation Instability in Microstructured Optical Fiber through Thermal Heating
2020
Broadband tuning of polarization modulation instability in microstructured optical fibers is reported. Tunability is achieved by simultaneous birefringence-dispersion changes through thermal heating. 906 cm-1 frequency tunability range is attained.
<title>Clinical potential of the side-glowing optical fibers</title>
1997
Unconventional designs of silica-core optical fibers providing efficient lateral emission through the cylindrical side surface have been developed and manufactured. A physical model of the side-glowing fibers, available experimental data and potential clinical applications of this type of lightguides are discussed. Promising, clinical applications can be expected in the following areas: (1) Phototherapy, including photo-dynamic therapy, soft-laser therapy and visible/UV broadband irradiation therapy. (2) Single-fiber laser Doppler flowmetry. (3) Laser-tissue dosimetry. (4) Linear and planar 'cold light' illumination. (5) Optical sensing of mechanical pressure.
Erbium doped optical fiber lasers for magnetic field sensing
2015
In this work two erbium doped optical fiber laser configurations for magnetic field measurement are implemented and compared. The first laser is set-up in a loop configuration and requires only a single FBG (Fiber Bragg Grating), acting as mirror. A second laser employs a simpler linear cavity configuration but requires two FBGs with spectral overlap to form the laser cavity. A bulk magnetostrictive material made of Terfenol-D is attached to the laser FBGs enabling modulation of its operation wavelength by the magnetic field. Moreover, a passive interferometer was developed to demodulate the AC magnetic field information where the corresponding demodulation algorithms were software based. B…
A frequency-output fiber optic voltage sensor with temperature compensation for power systems
2003
Abstract We present a frequency-output fiber optic voltage sensor for power systems with temperature compensated response. The sensor employs PZT-type ceramic tubes, which are interrogated by a length of single-mode fiber coiled onto the tubes and a Mach–Zehnder interferometer. The combination of piezoelectric tubes with properties exhibiting opposite behavior to temperature changes is successfully exploited to passively compensate the temperature sensitivity of the sensor. The prototype reported here exhibits a resolution of 13 mV rms and the deviations of the sensor’s response due to temperature changes are within 1% over the temperature range between −30 and 70 °C. The device presented h…
Stable Optically Generated RF Signals from a Fibre Mode-Locked Laser
2010
Phase stability of RF signals obtained by two-mode filtering of a fibre mode-locked laser is analyzed. Time jitter is shown to be constant with selected mode spacing, confirming the scheme capability for generating stable RF signals up to extremely-high frequency.
Polarization Modulation Instability in All-Normal Dispersion Microstructured Optical Fibers with sub-ns Pumping
2019
The advent of microstructured optical fiber (MOF) technology gave a significant boost to research in nonlinear optics. MOFs have the advantage of high nonlinearity and designable dispersion, which makes this type of fiber an excellent platform for efficient generation of nonlinear effects. In the last years, MOFs exhibiting normal dispersion at any guiding wavelength (ANDi fibers) aroused the interest because of the possibility of using them for the generation of coherent and recompressible supercontinuum (SC) light. In this contribution, we present our recent results regarding the generation of the polarization modulation instability (PMI) effect in ANDi MOFs in the quasi-CW pump regime at…
Enhanced supercontinuum generation in the nanosecond pump regime using specialty microstructured fibers
2009
Several alternatives have been investigated to achieve enhanced supercontinuum generation in the nanosecond pump regime using specialty silica-based microstructured optical fibers (MOFs). Among these alternatives we can point out the use of (a) MOF tapers, (b) highly Ge-doped core Y-shaped MOF and (c) Er-doped MOF. These specialty MOFs provide either an increased material nonlinear response or a rather small effective area, at the same time that the dispersion characteristics are adjusted to work at different excitation conditions. In our experiments, we have been using either a Q-switched Nd:YAG laser (10 Hz repetition rate) or an Yb-doped fiber laser (2 kHz repetition rate), both emitting…