Characteristics of monolithically integrated two-wavelength laser diodes with aluminum-free active layers

A two-wavelength integrated laser diode (TWINLD) with aluminum-free active areas (AAA) has been realized by monolithically combining two different laser material structures in a single chip utilizing the metalorganic chemical vapor deposition growth and regrowth techniques. The single TWINLD chip comprises two ridge wave-guide lasers, one is an InGaP/InGaAlP material structure for a 650 nm red laser, and another is an InGaAsP/AlGaAs material structure with AAA for a 780 nm infrared laser. The chip geometry is 300 μm long and 300 μm wide with a separation of 150 μm between two laser emission spots. The ridge widths are 3.5 and 2 μm for the red and IR laser, respectively, and both lasers emit a single transverse mode with a threshold current of 12 mA for a 650 nm laser and 14 mA for a 780 nm laser under continuous wave operation condition.