Single-pass UV generation at 222.5 nm based on high-power GaN external cavity diode laser

N. Ruhnke, A. Müller, B. Eppich, R. Güther, M. Maiwald, B. Sumpf, G. Erbert, and G. Tränkle

Published in:

Opt. Lett., vol. 40, no. 9, pp. 2127-2129 (2015).

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We demonstrate a compact system for single-pass frequency doubling of high-power GaN diode laser radiation. The deep UV laser light at 222.5 nm is generated in a β-BaB2O4 (BBO) crystal. A high-power GaN external cavity diode laser (ECDL) system in Littrow configuration with narrowband emission at 445 nm is used as pump source. At a pump power of 680 mW, a maximum UV power of 16 µW in continuous-wave operation at 222.5 nm is achieved. This concept enables a compact diode laser-based system emitting in the deep ultraviolet spectral range.

Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany

OCIS codes:

(140.2020) Diode lasers; (140.3515) Lasers, frequency doubled; (140.3610) Lasers, ultraviolet.