1.2 μm range GaInAs SQW lasers using Sb as surfactant

Highly strained Ga_0.61In_0.39As_ySb _1-y(y⩾0.995)/GaAs SQW lasers that incorporate a small amount of Sb have been successfully grown by gas-source molecular beam epitaxy (GSMBE). The lasing wavelength is 1.185 μm, and the threshold current density is as low as 280 A/cm², which is one of the lowest ever reported for 1.2 μm range GaInAs quantum film (QF) lasers. The lasing wavelength is the longest value ever reported for MBE-grown GaInAs/GaAs QF system to the best of the authors´ knowledge. It has been confirmed for the first time that Sb reacts in a highly strained GaInAs/GaAs system as a surfactant, which increases the critical thickness at which the growth mode changes from two-dimensional (2D) to three-dimensional (3D) growth