Researchers at Intel have pushed the boundaries of silicon photonics once again by developing the first avalanche photodetector (APD). This inexpensive silicon-based device promises to revolutionize how multiple processor cores communicate within computing systems. It uses standard silicon to transmit and receive optical data among computers and other electronic devices. It also stands to reduce costs and increase performance, next to commercially available optical devices.
|A ladybug crawls across an experimental
Avalanche Photodetector chip containing
silicon optical devices that are only
a fraction of a millimeter. (Credit: Intel)
In order to stay on top of data transfer speed game, Intel’s team suggests using optical technology as the only way to dramatically increase communication speeds between processor cores in the near future. Since the move to optical technology would require new components, Intel developed a silicon-based APD; a light sensor that achieves superior sensitivity by detecting light and amplifying weak signals as light is directed onto the silicon. “Intel’s APD converts the light beams into electrical signals,” said Yimin Kang, a senior researcher at Intel, who also added that until now manufacturers paid more than $100 for a single device of this type.
Kang also iterated that Intel’s motivation was to build a very low cost and robust device. This was achieved by using silicon, which is a very inexpensive commodity that produces very mature products.
|A packaged silicon Avalanche Photodetector.
The silicon chip is the grey square
in the center of the image. Wire bonds
connect the device to the package pins,
which in turn allow researchers to
interface the device with test equipment.
The new APD utilizes silicon and CMOS processing to fulfil a “gain-bandwidth product” of 340 GHz, which is the best result ever measured for the APD performance metric. This achievement proves that it is possible for a silicon photonics device to have data running at rates of 40Gbps or higher and have lower costs compared to more expensive optical materials such as indium phosphide.
The director of Intel’s Photonics Technology Lab, Dr. Mario Paniccia, recently said: “This research result is another example of how silicon can be used to create very high-performing optical devices.” He also iterated that other than optical communication, the silicon-based APDs could be employed in other fields such as sensing, imaging, quantum cryptography
, and biological applications; the team at Intel hopes to tackle future bandwidth requirements of data-intensive computing applications, like remote medicine and lifelike 3-D virtual worlds.
TFOT has previously covered Intel’s High Speed Optical Trinity
– the silicon-germanium optical detector that had combined a laser and an optical modulator “on a chip,” and also an article on booting up in an instant
, which is possible by installing a new program that circumvents Windows’ long boot-up time to just a few seconds.
Additional information on the Avalanche Photodetector (APD) can be found on Intel’s website.