The capacity is determined for an optical channel employing Pulse Position Modulation (PPM) and an Avalanche PhotoDiode (APD) detector. This channel is different from the usual optical channel in that the detector output is characterized by a Webb-plus-Gaussian distribution, not a Poisson distribution. The capacity is expressed as a function of the PPM order, slot width, laser dead time, averag...

*System Devices Research Laboratories †System Platforms Research Laboratories Two types of waveguide photodiodes (WG-PD)  an evanescently coupled photodiode (EC-WG-PD) and a separated-absorption-and-multiplication avalanche photodiode (WG-APD)  were developed for use in 40Gbps receivers. The EC-WG-PD is much more robust than a conventional WG-PD under high optical input operation because of i...

Two large-area, low noise, high speed fluorescence detectors have been built. One detector consists of a photodiode with an area of 28 mm x 28 mm and a low noise transimpedance amplifier. This detector has a input light-equivalent spectral noise density of less than 3 pW/ √ Hz, can recover from a large scattered light pulse within 10 μs, and has a bandwidth of at least 900 kHz. The second detec...

The Silicon Photomultiplier (SPM) addresses the challenge of detecting, timing and quantifying low-light signals down to the single-photon level. Traditionally the province of the Photomultiplier Tube (PMT), Avalanche Photodiode (APD), or PIN photodiode with high-gain amplifier, the Silicon Photomultiplier now offers a highly attractive alternative that closely mimics the low light detection ca...

Increasing reliance on the Internet places greater and greater demands for high-speed optical communication systems. Increasing their data transfer rate allows more data to be transferred over existing links. With optical receivers being essential to all optical links, bandwidth performance of key components in receivers, such as avalanche photodiodes (APDs), must be improved. The APDs rely on ...

An avalanche photodiode based (APD) detector for the visible wavelength range was developed for low light level, high frequency beam emission spectroscopy (BES) experiments in fusion plasmas. This solid state detector has higher quantum efficiency than photomultiplier tubes, and unlike normal photodiodes, it has internal gain. This paper describes the developed detector as well as the noise mod...