Planar InP/InGaAs avalanche photodetector with integrated dielectric wavelength filter

Patterned bandpass dielectric interference filters with centre wavelengths around 1.3 mu m have been applied to top-entry photodiodes to produce high-speed, high-responsivity, photodetectors for wavelength division multiplexing. The measured responsivity exceeded 25 A/W with a full width half maximum of 19 nm and peak rejection of over 25 dB.<>     

Integrated dielectric wavelength filters on InGaAs PIN photodetectors

There is an increasing desire to employ wavelength division multiplexing (WDM) techniques in optical communication systems to increase the useable capacity of optical fibre links. WDM transmitters usually consist of several narrow linewidth lasers, with their operating wavelengths suitably spaced. WDM demultiplexers or receivers employ either discrete gratings or discrete transmission filters to separate the various wavelengths. The disadvantage of such demultiplexers is that precise mechanical alignment of the many components is required. Together with the high cost of components such as gratings this makes such demultiplexers unsuitable for mass production. The authors describe a method of producing a dielectric wavelength filter integrated onto an InGaAs PIN photodiode for use in WDM systems and give results for the transmission characteristics of the filters and quantum efficiency of the whole structure.<>     

140 Mbit/s receiver performance at 2.4 μm using InAsSbP detector

A 140 Mbit/s optical receiver has been demonstrated using for the first time an InAsSbP photodetector operating at room temperature and optimised for operation at 2.4 μm, close to the minimum-loss wavelength of fluoride fibre. The receiver sensitivity was measured to be -32 dBm at 140 Mbit/s and 2.4 μm