Separate lateral confinement quantum well laser

A semiconductor quantum well laser structure formed on a buffer layer, comprising:

• a layered semiconductor structure including optical confinement layers;
• a buried heterojunction within said optical confinement layers, the buried heterojunction being dimensioned and arranged to confine injected carriers during laser operation;
• a ridge waveguide outside said optical confinement layers having an index step appropriate to attain desired lateral waveguide properties, the ridge waveguide being dimensioned and arranged with respect to said buried heterojunction to confine an optical mode during laser operation, wherein an index step created by the buried heterojunction is substantially removed from the optical mode.

A semiconductor quantum well laser structure, comprising semiconductor layers forming:

• a buried heterostructure separated from a ridge waveguide by a cladding;
• and
• an index step in said buried heterostructure outside of an index step of said ridge waveguide.

A semiconductor quantum well laser structure, comprising semiconductor layers forming:

• a buried heterostructure separated from a ridge waveguide by a cladding, wherein said buried heterostructure is laterally wider than said ridge waveguide.