INP-based monolithic integrated chaotic semiconductor laser chip capable of feeding back randomly diffused light

An InP-based monolithic integrated chaotic semiconductor laser chip capable of feeding back randomly diffused light, characterized in comprising:

• an N-type substrate;
• an InGaAsP lower confinement layer epitaxially grown on the N-type substrate;
• an undoped InGaAsP multiple quantum well active region layer epitaxially grown on the InGaAsP lower confinement layer;
• an InGaAsP upper confinement layer epitaxially grown on the undoped InGaAsP multiple quantum well active region layer;
• a heavily doped P-type InP cover layer, being ridge-shaped, and epitaxially grown in the middle of the InGaAsP upper confinement layer;
• a heavily doped P-type InGaAs contact layer located on the heavily doped P-type InP cover layer;
• a P+ electrode layer made on the heavily doped P-type InGaAs contact layer, and divided into four segments with three isolation grooves from left to right along an arrangement alignment of the P+ electrode layer;
• and an N+ electrode layer made on a back surface of the N-type substrate;
• wherein a first segment, a second segment, and a fourth segment of the P+ electrode layer, from left to right, respectively correspond to a left distributed feedback (DFB) semiconductor laser, a bidirectional semiconductor optical amplifier (SOA), and a right DFB semiconductor laser;
• a third segment of the P+ electrode layer, from left to right, sequentially corresponds to a left passive optical waveguide region, a doped passive optical waveguide region, and a right passive optical waveguide region;
• the InGaAsP upper confinement layer in the regions corresponding to the left DFB semiconductor laser and the right DFB semiconductor laser engraves distributed feedback Bragg gratings;
• and the doped passive optical waveguide region is doped with other doped particles.