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arXiv · 2412.01793

Quasi-continuous-wave-pumped thulium-doped fiber laser with 0.2 kW of instantaneous output power

Changshun Hou·Ziwei Zhai·Nilotpal Choudhury·Tom Harris·Jayanta K. Sahu·Johan Nilsson
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Abstract

A thulium-doped fiber laser operating quasi-continuous-wave generated 198 W of instantaneous output power in 0.2-ms pulses at 50 Hz repetition rate. The duty cycle becomes 1% and the average output power 2.0 W. This was cladding-pumped with 408 W from 0.79-um diode lasers (average pump power 4.1 W). The pump switch-on time was ~10 us at full power, with the laser exhibiting relaxation oscillations starting ~5 us after the start of the pumping and lasting for ~5 us. The slope efficiency with respect to absorbed pump power was 67% up to 200 W of absorbed pump power and 52% at the full 352 W of absorbed pump power. The low duty cycle simplified the heatsinking, despite the high instantaneous power and thermal load.

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Changshun Hou, Ziwei Zhai, Nilotpal Choudhury, Tom Harris, Jayanta K. Sahu, Johan Nilsson. 2024-12-02. Quasi-continuous-wave-pumped thulium-doped fiber laser with 0.2 kW of instantaneous output power. https://arxiv.org/abs/2412.01793

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