An apparatus having at least one integrated dual-channel buried waveguide (W), said apparatus further comprising: • a first cladding semi-conductor layer stack of a first conductivity type, • an active semi-conductor layer stack for producing at least one of optical gain and light emission, said active semi-conductor layer stack being formed on said first cladding semi-conductor layer and buried under • a second cladding semi-conductor layer stack of a second conductivity type, comprising at least one regrowth layer, - wherein said at least one integrated dual-channel buried waveguide (W) is formed along a longitudinal axis of the apparatus corresponding to an axis of light propagation and comprises at least one central stripe portion (S) having a width, said central stripe portion having a dual channel of two channels (C1, C2) of widths W isol1 , W isol2 respectively, each channel of the two channels (C1, C2) being formed along a respective side of said central stripe portion (S) and extending through said first cladding semi-conductor layer stack , said active semi-conductor layer stack , said second cladding semi-conductor layer stack , and said channels (C1, C2) being buried in a semi-conductor layer stack , and - wherein, on respective edges of the channels (C1, C2) which are opposite the central stripe portion (S), there are lateral zones (L1, L2) within which there are provided respective vertical trenches (T1, T2) perpendicular to the longitudinal axis of the apparatus and crossing through said semi-conductor layer stack , said second cladding semi-conductor layer stack to the level of said active semi-conductor layer stack , characterized in that said vertical trenches (T1, T2) extend longitudinally through the entire thickness of said active layer stack and laterally up to the edges of the channels (C1, C2) which are opposite the central stripe portion (S), so as to form a space (V1, V2) located in the respective lateral zones (L1, L2), each space (V1, V2) having the shape of an inverted T, as seen in a lateral cross section. • a first cladding semi-conductor layer stack of a first conductivity type, • an active semi-conductor layer stack for producing at least one of optical gain and light emission, said active semi-conductor layer stack being formed on said first cladding semi-conductor layer and buried under • a second cladding semi-conductor layer stack of a second conductivity type, comprising at least one regrowth layer, - wherein said at least one integrated dual-channel buried waveguide (W) is formed along a longitudinal axis of the apparatus corresponding to an axis of light propagation and comprises at least one central stripe portion (S) having a width, said central stripe portion having a dual channel of two channels (C1, C2) of widths W isol1 , W isol2 respectively, each channel of the two channels (C1, C2) being formed along a respective side of said central stripe portion (S) and extending through said first cladding semi-conductor layer stack , said active semi-conductor layer stack , said second cladding semi-conductor layer stack , and said channels (C1, C2) being buried in a semi-conductor layer stack , and - wherein, on respective edges of the channels (C1, C2) which are opposite the central stripe portion (S), there are lateral zones (L1, L2) within which there are provided respective vertical trenches (T1, T2) perpendicular to the longitudinal axis of the apparatus and crossing through said semi-conductor layer stack , said second cladding semi-conductor layer stack to the level of said active semi-conductor layer stack , <EOS>