论文信息 - Novel high-speed camera analysis of transverse mode instabilities in rod fiber amplifiers

Novel high-speed camera analysis of transverse mode instabilities in rod fiber amplifiers

In this work a novel accurate method of measuring beam fluctuations is presented and applied to analyze transverse mode instabilities (TMI). The new measurement, ST-measurement, uses Fourier analysis on data from a high-speed camera to achieve raw spatial information about beam fluctuations. TMI in a 65 μm mode- field-diameter aeroGain-ROD-PM85 fiber is investigated using both the ST- and standard photo detector measurement. A comparison of the two measurements shows the quantitative and qualitative superiority of the new ST-measurement due to the spatial information. Numerical simulations are carried out to support the interpretation of the data.

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