High performance long wavelength strained layer InGaAs/InP quantum well lasers

Strained-layer quantum-well InGaAsP/InP lasers emitting at wavelengths between 1.47 and 1.55 mu m are reported. The lasing wavelength could be adjusted by introducing either tensile or compressive strain as well as by changing the layer thickness of the quantum wells. To obtain a lasing wavelength as short as 1.47 mu m, tensile strain is preferable due to the relaxed constraints in layer thickness of the quantum wells. Both tensile and compressive strain were found to improve the performance of the lasers as compared to the lattice-matched ones. A sample with compressive strain showed a CW threshold current as low as 4 mA. Maximum CW output power as high as 206 mW with a lasing wavelength of 1.47 mu m was obtained from a quantum-well active layer with tensile strain.<>