Output beam characteristics of 1.3 µm GaInAsP/InPSL-QW lasers with narrow and circular output beam

Abstract
It is verified that the output beam for lasers with a mode-field converter is quite stable against output power up to 30 mW and operating temperature up to 70°C. The threshold current and differential quantum efficiency of an HR-coated device are 14 mA and 45%, respectively. The FWHMs of the FFPs parallel and perpendicular to the junction plane are as small as 10 and 11°, respectively.