The sensitivity of early fiber-optic gyroscopes (FOG) fell short of the theoretical limit. The use of certain configurations, fiber components, and well designed optical sources can help the FOG reach this limit. Sources for the FOG must be broadband, spatially coherent and high power. They must produce a mean wavelength which is stable with respect to temperature and feedback from system components. Additionally, they must emit at long wavelengths, where silica fibers are insensitive to radiation induced losses.; Two approaches to broadband, 1.55 {dollar}mu{dollar}m, erbium-doped fiber sources for the FOG are considered. The most promising approach is the superfluorescent fiber source (SFS), which utilizes amplification of spontaneous emission in a single pass or in two passes through the fiber, without a resonant cavity. Such sources have produced more than 50% conversion of pump photons near 980 nm or 1.48 {dollar}mu{dollar}m to source photons. Laser diode pumping in these pump bands is explored in detail. Depending on fiber length, pump power, pump wavelength and SFS configuration, emission bandwidths between 8 and 27 nm are measured. The thermal coefficient of the mean wavelength of the SFS is consistently below 10 ppm/{dollar}spcirc{dollar}C, and near 0 ppm/{dollar}spcirc{dollar}C for certain design choices. The pump wavelength and pump power are optimized to minimize the dependence of the mean wavelength on these temperature dependent quantities. The detrimental effects of feedback are reduced through optical isolation and the proper choice of FOG configuration. Issues such as the effects of multiple pump modes and loss mechanisms are treated by use of computer simulations.; The broadband Er-doped wavelength-swept fiber laser (WSFL) is presented as an alternative to the SFS. This source utilizes an intracavity acousto-optic modulator to sweep the emission of an Er-doped laser across the gain curve of erbium. Theoretical and measured characteristics of such sources are discussed. Emission bandwidths exceeding 20 nm have been demonstrated. The dynamic response of the WSFL and its coherence in an integrating system has been measured. The WSFL has the potential for higher efficiency and for greater control of the emitted spectrum, but it is more complex than the SFS.
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