Current and Temperature Dependencies of Internal Optical Loss in Laser Heterostructures

Free carrier absorption in heterostructure layers of an operating laser diode has been measured. The proposed technique is based on coupling pulse probe light emission into the laser waveguide. Lasers with various heterostructure designs were measured at different current and temperature levels up to 30 kA/cm
²
and 85°C. The dependencies sufficiently describe the laser characteristics and can be used for heterostructure design comparison and optimization.