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The Spaser Nanolaser

Surface plasmon resonance lasers are the smallest nanolasers yet

3 min read

In the quest to make computer processors smaller and faster, computing with light instead of relatively slow electrons has long been a tantalizing goal. One roadblock has been the inability to make lasers tiny enough so that several thousand of them could fit easily on a chip. In late August, two groups of researchers reported the construction of a new kind of nanometer-scale laser. Surface plasmon resonance nanolasers, or spasers, are the smallest lasers yet made, and their creators say the devices could pave the way toward ultrafast optical computing.

Spasers can "bridge the worlds of electronics and optics at truly molecular-length scales," says mechanical engineering professor Xiang Zhang, of the University of California, Berkeley, who led one of the groups with research associate Rupert Oulton.

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Two Startups Are Bringing Fiber to the Processor

Avicena’s blue microLEDs are the dark horse in a race with Ayar Labs’ laser-based system

5 min read
Diffuse blue light shines from a patterned surface through a ring. A blue cable leads away from it.

Avicena’s microLED chiplets could one day link all the CPUs in a computer cluster together.


If a CPU in Seoul sends a byte of data to a processor in Prague, the information covers most of the distance as light, zipping along with no resistance. But put both those processors on the same motherboard, and they’ll need to communicate over energy-sapping copper, which slow the communication speeds possible within computers. Two Silicon Valley startups, Avicena and Ayar Labs, are doing something about that longstanding limit. If they succeed in their attempts to finally bring optical fiber all the way to the processor, it might not just accelerate computing—it might also remake it.

Both companies are developing fiber-connected chiplets, small chips meant to share a high-bandwidth connection with CPUs and other data-hungry silicon in a shared package. They are each ramping up production in 2023, though it may be a couple of years before we see a computer on the market with either product.

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