Abstract: In one aspect the invention relates to a high bandwidth shallow mesa semiconductor photodiode responsive to incident electromagnetic radiation. The photodiode includes an absorption narrow bandgap layer, a wide bandgap layer disposed substantially adjacent to the absorption layer, a first doped layer having a first conductivity type disposed substantially adjacent to the wide bandgap layer, and a passivation region disposed substantially adjacent to the wide bandgap layer and the first doped layer.

Abstract: An optical transponder/transceiver for intermediate range (e.g., 10-50 km) optical communication applications utilizes an electroabsorption modulated laser for the transmitting device. Preferably, the laser operations at a wavelength of approximately 1310 nm and comprises an electroabsorption modulated Fabry-Perot laser.

Abstract: In one aspect, the invention is an optical fiber having a modified geometry. The optical fiber includes an optical fiber portion. The optical fiber portion can have a first fiber end face and a cylindrical fiber surface encircling the first fiber end face. The optical fiber having a modified geometry also includes a contoured surface formed from the first fiber end face. The contoured surface does not extend beyond the cylindrical fiber surface. A reflective coating disposed on the contoured surface and an optical transmission region formed from a portion of the cylindrical fiber surface are also included in the optical fiber having a modified geometry.

Abstract: In one aspect, the invention relates to a waveguide structure for differential transmission lines. The waveguide structure includes a first ground structure, a first signal line, a second ground structure, a second signal line, a third ground structure. The first signal line is typically positioned adjacent and substantially parallel to the first ground structure. The second ground structure has a first separation distance from the first ground structure and is typically positioned adjacent and substantially parallel to the first signal line. The first signal line is typically positioned between both the first and second ground structures. The second signal line typically a has a second separation distance from the first signal line and is positioned adjacent and substantially parallel to the second ground structure. The second ground structure is typically positioned between both the first and second signal lines.

Abstract: In one aspect the invention relates to a high bandwidth shallow mesa semiconductor photodiode responsive to incident electromagnetic radiation. The photodiode includes an absorption narrow bandgap layer, a wide bandgap layer disposed substantially adjacent to the absorption layer, a first doped layer having a first conductivity type disposed substantially adjacent to the wide bandgap layer, and a passivation region disposed substantially adjacent to the wide bandgap layer and the first doped layer.

Abstract: An electroabsorption modulated laser (EML) is formed to include a Fabry-Perot lasing section, in place of the conventional DFB lasing section. When operated at a wavelength of 1310 nm, the wider spectral bandwidth of the FP device (containing several longitudinal modes) is of no concern, since 1310 nm is the zero dispersion wavelength of most conventional transmission fibers. A selective area growth process is used to simultaneously form the MQW active regions of both the FP and EA sections of the EML device, and an isolation trench may be formed between the sections to reduce the effects of electrical crosstalk.