Thermal effects in kilowatt all-fiber MOPA

Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China.
Optics Express (Impact Factor: 3.49). 08/2011; 19(16):15162-72. DOI: 10.1364/OE.19.015162
Source: PubMed

ABSTRACT Thermal effects and output power characteristics of kilowatt all-fiber master-oscillator power amplifier (MOPA) are investigated. Proper designs for cooling apparatus are proposed and demonstrated experimentally, for the purpose of minimizing splice heating which is critical for the reliability of high power operation. By using these optimized methods, a thermal damage-free, highly efficient ytterbium-doped double-clad fiber MOPA operating at 1080 nm with 1.17 kW output was obtained. The maximum surface temperature at the pump light launching end splice of the booster amplifier was 345 K, and the temperature rise for this key splice was 0.052 K/W.

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    • "It results in difficulties in coupling, especially in the case where it is necessary to launch pulse with high energy or peak power into the fiber. Actually, if we use the near-IR pump source to pump very short fiber to generate SC covering mid-IR, the launched pulse energy or peak power had better be as high as possible, and therefore the delicate microstructure in the pump facet of fiber is subject to damage [6]. "
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