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arXiv · 1510.01910

Overcoming Bifurcation Instability in High-Repetition-Rate Ho:YLF Regenerative Amplifiers

Peter Kroetz·Axel Ruehl·Gourab Chatterjee·Anne-Laure Calendron·Krishna Murari·Huseyin Cankaya·Peng Li·Franz X. Kaertner·Ingmar Hartl·R. J. Dwayne Miller
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Abstract

We demonstrate a Ho:YLF regenerative amplifier (RA) overcoming bifurcation instability and consequently achieving high extraction energies of 6.9 mJ at a repetition rate of 1 kHz with pulse-to-pulse fluctuations of 1.1%. Measurements of the output pulse energy, corroborated by numerical simulations, identify an operation point that allows high-energy pulse extraction at a minimum noise level. Complete suppression of the onset of bifurcation was achieved by gain saturation after each pumping cycle in the Ho:YLF crystal via lowering the repetition rate and cooling the crystal. Even for moderate cooling, a significant temperature dependence of the Ho:YLF RA performance was observed.

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Peter Kroetz, Axel Ruehl, Gourab Chatterjee, Anne-Laure Calendron, Krishna Murari, Huseyin Cankaya, Peng Li, Franz X. Kaertner, Ingmar Hartl, R. J. Dwayne Miller. 2015-10-07. Overcoming Bifurcation Instability in High-Repetition-Rate Ho:YLF Regenerative Amplifiers. https://doi.org/10.1364/ol.40.005427

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