Educação matemática pela arte
Gusmão, Lucimar Donizete
2013-08-28
Search results
131 records were found.
Recently a new class of optical fibre has emerged: the microstructured fibre. One example is the holey fibre (HF), which has a cladding region defined by air holes (see Figure 1). Light is guided in a HF due to the effective refractive index contrast between the solid core and the holey cladding. This contrast is typically a strong function of wavelength, and this leads to a host of novel optical properties. [1,2] Microstructured, fibres offer new alternatives for sensing, and they can be divided into two categories: those which use the holes directly, and those which exploit their unusual optical properties.
Microstructured optical fibers are of increasing interest since they offer unique optical properties and design flexibility that cannot be achieved in conventional forms of fiber. We review structural features, fabrication, optical properties and potential applications of index-guiding holey optical fibers. The state-of-the-art is presented for both silica and compound glass holey fibers.
© Copyright 2001 IEEE
Microstructured optical fibres (i.e. fibres that contain holes) have assumed a high profile in recent years, and given rise to many novel optical devices. The problem of manufacturing such fibres by heating and then drawing a preform is considered for the particularly simple case of annular capillaries. A fluid-mechanics model is constructed using asymptotic analysis based on the small aspect ratio of the capillary. The leading-order equations are then examined in a number of asymptotic limits, many of which give valuable practical information about the control parameters that influence the drawing process. Finally, some comparisons with experiment are performed. For a limited set of experiments where the internal hole is pressurised, the theoretical predictions give qualitatively accurate results. For a much more detailed set of exper...
We report soliton pulse formation and amplification and soliton-self-frequency shifting in an anomalously dispersive, Yb 3+ -doped holey fiber amplifier seeded with pulses from an Yb 3+ -doped, 1.06-m fiber based mode-locked oscillator. Our fiber-based system provides a highly practical, all-diode-pumped, continuously tunable femtosecond pulse source operational in the important and difficult to reach wavelength range from 1.06 to 1.33 m. In other experiments multipulse, multicolored soliton formation was observed with wavelength-shifted pulsed output to beyond 1.58 m. Supercontinuum generation and nonlinear compression of pulses to 65 fs were also obtained with other configurations.
We demonstrate a spectrally sliced pulse source which utilizes supercontinuum generated in a normally dispersive holey fiber and spectral slicing in an arrayed waveguide grating. All 36 10-GHz channels exhibit almost constant pulsewidth and excellent noise properties, as verified by bit-error-rate measurements.
An optical fibre containing a selection of independently addressable air-clad cores with different dimensions is presented. The intrinsic properties of such an assorted core fibre are studied and potential applications are reviewed. The physical dimensions required for guidance at various wavelengths are explored
Extremely large mode area fibers that are single-moded over a broad wavelength range can be created using holey fiber technology. However, as with any fiber, the largest mode areas that are practically feasible are ultimately determined by bending losses. It is therefore essential to gain an understanding of the factors that influence bend loss in these fibers in order to form accurate predictions that can facilitate improved bend loss design. Here, we present the first detailed study of transition loss and pure bend loss in a holey fiber, and consider the impact of the fiber structure. A theoretical model is derived that retains the full refractive index profile of a holey fiber. This approach is used to predict the bend loss in large mode area holey fibers and is validated through comparison with experimental data. For the fibers und...
The authors report the fabrication of a polarisation-maintaining, high-nonlinearity, anomalously dispersive, Yb3+ doped holey fibre and describe what they believe to be the first demonstration of a modelocked holey fibre laser.
Little information exists regarding how large-mode holey fibers compare, in practical terms, with their conventional counterparts. We present what is to our knowledge the first experimental study of mode area and bend loss for a range of large-mode holey and conventional fibers. It is demonstrated here that large-mode holey fibers exhibit mode areas and bending losses that are comparable to those of conventional fibers at 1.55μm. However, the novel wavelength dependence of the numerical aperture in a holey fiber offers a significant advantage for broadband and short-wavelength applications in which single-mode operation is required.
