We present a membrane external-cavity surface-emitting laser (MECSEL) operating around 825 nm at room temperature. With a tuning range of 22 nm, the MECSEL fills the spectral gap between 810 nm and 830 nm, and extends the wavelength coverage of this category of high-beam-quality semiconductor lasers. For high-power operation, the pump spot size and cavity mode size can be enlarged in MECSELs. We apply this technique and demonstrate power scaling. The maximum output power is increased from 0.7 W to 1.4 W. Investigations on the beam quality reveal thermal lensing with a marginally changing $ {M^2} $ value close to the diffraction limit.

中文翻译：

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825 nm发射膜外腔表面发射激光器中的功率缩放和热透镜

我们提出了一种膜外腔表面发射激光器（MECSEL），在室温下工作于825 nm左右。MECSEL的调谐范围为22 nm，可填补810 nm至830 nm之间的光谱间隙，并扩展了这类高光束质量半导体激光器的波长范围。对于大功率操作，可以在MECSEL中扩大泵的光斑尺寸和腔模尺寸。我们应用此技术并演示功率缩放。最大输出功率从0.7 W增加到1.4W。对光束质量的研究表明，热透镜在接近衍射极限的附近出现$ {M ^ 2} $的变化。