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Digital Data Written in Stone

The "Digital Rosetta Stone" would store data and give wireless access to it for 1000 years

3 min read
Digital Data Written in Stone

17 June 2009—What do data archivists have in common with monarch butterflies, salmon, and most geese? They are always preparing for their next migration. From magnetic tape through hard disks, floppy disks, CDs, DVDs, and Blu-ray, digital data formats change periodically, forcing archivists to migrate their data before obsolescence or end-of-lifetime sets in. But now Tadahiro Kuroda, a research engineer and professor at Keio University, in Yokohama, Japan, and his team have come up with a device that could put an end to this recurring—not to mention costly—upheaval in data preservation by maintaining the data safely in an unchanging format that’s predicted to last 1000 years.

The device is a permanent memory system based on semiconductor technology. The prototype consists of four stacked 300-millimeter silicon wafers incorporating 2.5 terabits, (320 gigabytes), of data encoded on read-only memory and fabricated using a 45-nanometer complementary metal-oxide-semiconductor (CMOS) process, together with a separate data reader. Data is written on the chips using an electron beam, and the package is sealed with silicon-based film to prevent erosion.

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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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