Semiconductor Laser Diode

A semiconductor laser diode is disclosed. In an embodiment a semiconductor laser diode includes a semiconductor layer sequence having at least one active layer and a ridge waveguide structure having a ridge extending in a longitudinal direction from a light output surface to a rear side surface and being delimited by ridge side surfaces in a lateral direction perpendicular to a longitudinal direction, wherein the ridge has a first region and a second region adjacent thereto in a vertical direction perpendicular to the longitudinal and lateral directions, wherein the ridge includes a first semiconductor material in the first region and at least one second semiconductor material different from the first semiconductor material in the second region, wherein the ridge has a first width in the first region, and wherein the ridge has a second width in the second region, the second width being larger than the first width.