Thermal optimization of second harmonic generation at high pump powers

Published in:
Opt. Express, vol. 19, no. 23, pp. 23029-23035 (2011).
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Abstract:
We measure the temperature distribution of a 3 cm long periodically poled LiNbO₃ crystal in a single-pass second harmonic generation (SHG) setup at 488 nm. By means of three resistance heaters and directly mounted Pt100 sensors the crystal is subdivided in three sections. 9.4 W infrared pump light and 1.3 W of SHG light cause a de-homogenized temperature distribution of 0.2 K between the middle and back section. A sectional offset heating is used to homogenize the temperature in those two sections and thus increasing the conversion efficiency. A 15% higher SHG output power matching the prediction of our theoretical model is achieved.

OCIS codes:
(140.2020) Diode lasers; (140.3515) Lasers, frequency doubled; (190.2620) Harmonic generation and mixing; (140.6810) Thermal effects.

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