An edge emitting semiconductor laser comprising an active, radiation-generating zone (1), and an common waveguide (8), which is suitable for guiding the radiation generated in the active zone (1) within the semiconductor laser. The common waveguide (8) comprises a first n-doped layer (4) and a second n-doped layer (5), which is arranged between the first n-doped layer (4) and the active zone (1), wherein the refractive index n2 of the second n-doped layer (5) is greater than the refractive index n1 of the first n-doped layer (4) by a value dn.