DISTRIBUTED FEEDBACK (DFB) LASER WITH SLAB WAVEGUIDE

摘要

A distributed feedback (DFB) laser includes a substrate of a compound semiconductor material, and quantum-well (QW) active layer(s) overlying the substrate. A p-doped cladding layer including the compound semiconductor material is on one side of the active layer and an n-doped cladding layer is on the other side. A grating is in one of the cladding layers configured to select an operating wavelength for the DFB laser. A waveguide structure in the n-doped cladding layer includes a waveguide layer of a first composition compositionally different from the compound semiconductor material having an optical thickness of 0.7 to 1.5 of the guided wavelength. The waveguide structure can further include a hetero-waveguide stack including a plurality of alternating compositional layers beyond the waveguide layer each having a thickness between one quarter and one half the guided wavelength alternating the compound semiconductor material with a second composition defining a composition wavelength.

主权项

1. A distributed feedback (DFB) laser, comprising:
a substrate comprising a compound semiconductor material; at least one quantum-well (QW) active layer (active layer) overlying said substrate; a p-doped cladding layer comprising said compound semiconductor material on one side of said active layer; an n-doped cladding layer comprising said compound semiconductor material on another side of said active layer; a diffraction grating in said p-doped cladding layer or in said n-doped cladding layer configured to select an operating wavelength for said DFB laser, and a waveguide structure in said n-doped cladding layer including a waveguide layer comprising a first composition that is compositionally different from said compound semiconductor material, said waveguide layer having an optical thickness of 0.7 to 1.5 of said operating wavelength in said compound semiconductor material (guided wavelength).