Surface-emitting laser device

A surface-emitting laser device comprising:

• a first electrode;
• a first cladding layer of a first conductivity type electrically connected to the first electrode;
• an active layer provided on the first cladding layer;
• a second cladding layer of a second conductivity type provided on the active layer;
• a relaxation layer of a second conductivity type provided on the second cladding layer;
• a contacting layer of a second conductivity type provided on the relaxation layer and having a bandgap different from that of the second cladding layer;
• a second electrode provided on the contacting layer to be in ohmic contact with the contacting layer;
• and
• a resonance mode forming layer provided between the first cladding layer and the active layer or between the active layer and the second cladding layer, including a basic region and a plurality of different refractive index regions, in which the plurality of different refractive index regions have a refractive index different from that of the basic region, and in which the plurality of different refractive index regions are distributed two-dimensionally in a plane perpendicular to a thickness direction to form a resonance mode of light in the plane,
• wherein the relaxation layer has a bandgap width of that is between a bandgap width of the second cladding layer and a bandgap width of the contacting layer.