Semiconductor laser having reduced temperature dependence.

摘要

In accordance with the present invention a semiconductor laser is provided with a cavity having decreasing loss with increasing wavelength in order to reduce temperature dependence. Decreasing loss can be provided, for example, by provision of appropriate multilayer reflection coatings (18-25) or by longitudinal gratings that favour longer wavelengths. The coatings advantageously have peak reflectivity centered at the lasing wavelength corresponding to maximum operating temperature. The result in long wavelength InGaAs lasers is an improvement in the threshold temperature coefficient from about 50K to about 85K. In addition, the improved lasers exhibited a decreased rate of quantum efficiency degradation with temperature. <IMAGE>