An integrated tapered diode laser arrangement comprises an injector region (2) and a region (3) which is optically coupled to the injector region and expands in a cross section. At least one of said regions (2, 3) has a quantum well structure with a plurality of semiconductor materials, wherein the semiconductor materials are intermixed at least in one region (21, 31). The intermixed region (21, 31) has a larger electrical band gap than a non-intermixed region.