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arXiv · 1301.0234

Kerr-lens Mode Locking Without Nonlinear Astigmatism

Shi Yefet·Valery Jouravsky·Avi Pe'er
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Abstract

We demonstrate a Kerr-lens mode locked folded cavity using a planar (non-Brewster) Ti:sapphire crystal as a gain and Kerr medium, thus cancelling the nonlinear astigmatism caused by a Brewster cut Kerr medium. Our method uses a novel cavity folding in which the intra-cavity laser beam propagates in two perpendicular planes such that the astigmatism of one mirror is compensated by the other mirror, enabling the introduction of an astigmatic free, planar-cut gain medium. We demonstrate that this configuration is inherently free of nonlinear astigmatism, which in standard cavity folding needs a special power specific compensation.

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Shi Yefet, Valery Jouravsky, Avi Pe'er. 2013-01-02. Kerr-lens Mode Locking Without Nonlinear Astigmatism. https://doi.org/10.1364/josab.30.000549

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