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A New Phase in Nonvolatile Memory?

A possible successor to flash emerges from the shadows

4 min read

The first successful rewritable nonvolatile memory, flash, is a mainstay in numerous devices that require data to be retained when the equipment is switched off: cellphones, digital cameras, and PDAs. Flash chips represent a big market--US $15 billion to $17 billion.

Flash doesn't do well, however, at writing very large quantities of data quickly. It also begins to leak charge after several hundred thousand cycles, making it unsuitable for devices like a computer's main memory in which data are constantly rewritten. So it's not surprising that a lot of technologies are vying to be the premier next-generation nonvolatile memory, including polymer ferroelectric memories, magnetic RAM, and nanowires. But by a growing expert consensus, the most likely candidate to succeed flash memories is a technology based on phase-change materials.

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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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