For the first time, we present the measurement of the stimulated Brillouin gain spectra of all-glass, metal coated, doubleclad, large-mode area fibres. We describe the methodology used to measure the small SBS gains produced by the short lengths of large-mode area fibres. The Brillouin spectra of the fibres were also measured while a segment was heated on a hot plate. Sections of the metal coated fibres were raised to 250 °C, resulting in a ~0.2 GHz shift in the Brillouin gain peak. This is a significantly larger shift in temperature than possible with conventional polymer coated double clad fibres, demonstrating how metal coated fibres can begin to overcome some of the limiting nonlinearities associated with single frequency and narrow linewidth operation.
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