Low threshold 1.55 μm wavelength InAsP/InGaAsP strained multiquantum well laser diode grown by chemical beam epitaxy

Abstract

By using chemical beam epitaxy at growth temperatures as low as 460–480 °C, we have overcome strain relaxation problems that prevented so far the successful use of InAsP quantum wells in 1.55 μm lasers. Five quantum well InAsP/InGaAsP horizontal cavity lasers showed 88% internal efficiency, 1.6 cm−1 losses per well, and 33 A/cm2 transparency current density per well, which equal or even surpass the best published characteristics for 1.55 μm wavelength lasers based on any material system. Moreover, up to 17 quantum wells were integrated in a strain-balanced laser, which showed equally good characteristics.