Waveguide heterostructure for dispersion compensation in semiconductor laser
AssigneeEth Zürich
InventorsJérôme Faist, Yves Bidaux, Filippos Kapsalidis
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Abstract
A waveguide heterostructure for a semiconductor laser with an active part, comprising an active region layer depending of the type of semiconductor used, which is sandwiched between an electrode layer and a substrate, usable for dispersion compensation in a semiconductor laser frequency comb setup, an optical frequency comb setup and a manufacturing method.
Claims18
A waveguide heterostructure for a semiconductor laser with an active part, comprising an active region layer depending on the type of semiconductor used, which is sandwiched between an electrode layer and a substrate, usable for dispersion compensation in a semiconductor laser frequency comb setup,
- wherein a passive part, comprising at least an intercladding layer and a passive part top cladding surrounding a passive core layer, the passive part being inserted into the sandwich between the substrate and the electrode layer in a direction of a growth axis on top of or below the active part, wherein the intercladding layer, the passive part top cladding and the passive core layer are semiconductors and the refractive indices of the active region layer and of the passive core layer are greater than the refractive indices of the intercladding layer and of the passive part top cladding,
- wherein the active part and the passive part together form a coupled waveguide by coupling between a primary waveguide, whose core is the active region layer, and a secondary waveguide, whose core is the passive core layer, said coupling changing what would otherwise be respective uncoupled fundamental modes of the primary and secondary waveguides into an antisymmetric mode and a symmetric mode, the antisymmetric mode having a lower group velocity dispersion than that of the fundamental mode of the primary waveguide as well as having a larger overlap with the active region layer than that of the symmetric mode, so that the antisymmetric mode is selected for lasing.
A method of manufacturing a waveguide heterostructure for a semiconductor laser, the method comprising:
- providing a waveguide heterostructure comprising:
- an active part, comprising an active region layer depending on the type of semiconductor used, which is sandwiched between an electrode layer and a substrate, and
- a passive part, comprising at least an intercladding layer and a passive part top cladding surrounding a passive core layer, the passive part being inserted into the sandwich between the substrate and the electrode layer in the direction of the growth axis on top of or below the active part,
- wherein the intercladding layer, the passive part top cladding and the passive core layer are semiconductors and the refractive indices of the active region layer and of the passive core layer are greater than the refractive indices of the intercladding layer and of the passive part top cladding, and
- wherein the active part and the passive part together form a dual-coupled waveguide by coupling between a primary waveguide, whose core is the active region layer, and a secondary waveguide, whose core is the passive core layer, said coupling changing respective uncoupled fundamental modes of the primary and secondary waveguides into an antisymmetric mode and a symmetric mode, the antisymmetric mode having a lower group velocity dispersion than the fundamental mode of the primary waveguide as well as having a larger overlap with the active region layer than the symmetric mode, so that the antisymmetric mode is selected for lasing.
Dependencies are inferred from the claim text.