Laser diode comprises an active layer; a waveguiding region at least partially surrounding the active layer; a rear facet; a front facet designed for outcoupling laser radiation, wherein the active layer extends at least partially along a first axis (X) between the rear facet and the front facet; and a grating operatively connected to the waveguiding region, wherein the grating comprises a plurality of bridges and trenches designed such that an average increase of a coupling parameter P for the plurality of trenches along the grating is non-zero, wherein the coupling parameter P of a trench is defined by the equation, wherein dres is a distance of the trench to the active layer, w is a width of the trench and Δn is the refractive index difference between a refractive index of the trench and a refractive index of a material surrounding the trench.