Very low threshold current density of 1.3-μm-range GaInNAsSb-GaNAs3 and 5 QWs lasers

The dependence of the threshold current density on the number of wells for 1.3-μm-range edge emitting lasers using GaInNAsSb novel material, at which the incorporation of the small amount of Sb make the two-dimensional growth condition wide, is studied. The lowest record ever reported for the threshold current density per well (Jth A/cm²/well@L=900 μm) for 3 QWs lasers was achieved. GaInNAs-based 5 QWs lasers with the very low threshold current density per well of 160 A/cm² were successfully grown for the first time. Therefore, no significant deterioration of Jth is observed even though the number of wells increased up to 5. Since Jth of 5 QWs doesn´t increased rapidly compared to SQW and 3 QWs as decreasing the cavity length, it is considered that lower Jth can be obtained by utilizing 5 QWs in devices such VCSELs which use short cavity length.