Abstract: A transmit optical subassembly (TOSA) includes a spot-size-converted (SSC) semiconductor laser coupled to an optical fiber without a lens or isolator. The spot-size-converted semiconductor laser includes an active region and an expander region that expands the spot size of the laser while maintaining efficient active laser performance. The SSC laser is coupled to a submount and passively aligned to an optical fiber positioned within a V-shaped groove formed within the submount. The SSC laser includes a narrow far field advantageous for providing a high coupling efficiency and high quality data transmission. The SSC laser is resistant to back reflection and produces a 1.3 or 1.55 micron optical wavelength and a data rate ranging from 1 to 10 Gbps. The TOSA provides high coupled power due to narrow far field, with potential extra reflection resistance due to absorption and mode transfer losses in coupling reflections through the expander back into the active region.

Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) (10) and a method for manufacturing the VCSEL (10). The VCSEL (10) includes a ridge structure (34), a first confinement layer (36) disposed adjacent to a portion of the ridge structure (34), and a second confinement layer (37) disposed on the first confinement layer (36) and disposed adjacent to a portion of the ridge structure (32). Carriers injected into the ridge structure (34) are confined by the first confinement layer (36).

Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) (10) and a method for manufacturing the VCSEL (10). The VCSEL (10) includes a ridge structure (34), a first confinement layer (36) disposed adjacent to a portion of the ridge structure (34), and a second confinement layer (37) disposed on the first confinement layer (36) and disposed adjacent to a portion of the ridge structure (32). Carriers injected into the ridge structure (34) are confined by the first confinement layer (36).

Abstract: A method for biasing a semiconductor laser (12) at the threshold level of the semiconductor laser (12). The method includes applying pilot tone signals having the same frequency to a bias current and a drive current of the semiconductor laser (12). A lateral detector (13) generates a photocurrent from spontaneous emissions of the semiconductor laser (12). Further, the method includes biasing the semiconductor laser (12) using a pilot tone signal of the photocurrent.