A method for improving the efficiency for an optoelectronic device, such as semiconductor lasers, Superluminescence Light Emitting Diodes (SLDs), Gain Chips, optical amplifiers is disclosed, see FIG. 4B. In accordance with the principles of the invention, at least one blocking layer (70) is interposed at the interface between materials composing the device. The at least one blocking layers creates a barrier that prevents the leakage of electrons from a device active region contained in the waveguide region, to a device clad region (66). In one aspect of the invention, a blocking layer (70) is formed at the junction of the semiconductor materials having different types of conductivity. The blocking layer prevents electrons from entering the material of a different polarity. In another aspect of the invention, a low-doped or undoped region (64) is positioned adjacent to the blocking layer (70) to decrease optical losses.