IBM Creates On-Chip Nanophotonic Switch
David Lammers, News Editor -- Semiconductor International, 3/17/2008 9:50:00 AM
IBM researchers based at the T.J. Watson Research Laboratory (Yorktown Heights, N.Y.) have succeeded in using optical pulses to create a nanophotonic switch, the latest advance in the company’s overall effort to create on-chip optical interconnects.
By using light instead of copper wires, IBM estimates that ~100× more information can be sent between processor cores while using 10× less power and generating less heat.
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| Photonic switches can transfer data at >1 Tb/sec among processor cores, according to IBM. |
As many as 2000 of the switches can be built in an area of 1 mm2, the company said. By simultaneously switching many different wavelengths of light, the nanophotonic switch is able to route large amounts of data in a multi-core processor. Each wavelength can switch data at 40 Gb/sec, making it possible to switch at an aggregate bandwidth >1 Tb/sec.
The IBM scientists also reported that the optical switch can operate in real-world environments where hot spots can radically change the operating temperature of the switches. The IBM switches have a temperature-drift tolerant operation, which the company said is “one of the most critical requirements for on-chip optical networks.”
“This new development is a critical addition in the quest to build an on-chip optical network,” said Yurii Vlasov, manager of silicon nanophotonics at the Watson Research Center. “In view of all the progress that this field has seen over the last few years, it looks as if our vision for on-chip optical networks is becoming more and more realistic.”
In November 2005, IBM scientists demonstrated a silicon nanophotonic device that could actively control the speed of light. In December 2006, a silicon device was used to demonstrate buffering of over one byte of information encoded in optical pulses. Buffering is a key requirement for building on-chip optical interconnections.
In December 2007, IBM scientists announced the development of an ultracompact silicon electro-optic modulator, which converts electrical signals into pulses of light.
A paper titled, “High-Throughput Silicon Nanophotonic Wavelength-Insensitive Switch for On-Chip Optical Networks,” by Vlasov, William M.J. Green and Fengnian Xia was published in the journal Nature Photonics.
