they claim to increase the speed to 500Mbps in 3-5 years. but femtosecond laser is not semiconductor. there is no exponential scaling law.

femtosecond laser has been running at 80MHz for decades, they cannot just talk to the laser manufacture and ask them casually to increase that to 500MHz or above. so, it is better to take a grain of salt of the claim speed can be increase to 500Mbps in 5 years.

The cost of the femtosecond laser also won't come down easily either. At $75k a pop for the laser alone, who can afford such technology?

We have GHz femtosecond lasers. It's commercialized! Amplitude Systemes has them for sale! We build time references out of them!

You can also make them out of semiconductors. VCSELs and other semiconductor gain media naturally have short upper state lifetimes. It makes for a happy stable femtosecond laser with a semiconductor saturable absorber.

Surely the only intended customers are giant organizations with petabytes of data. Millions of dollars for their archival system does not seem unreasonable. I recall reading a story that movie studios refresh their physical media for their archives every N years to prevent data loss. If these slabs of glass are stable that removes an ongoing operational burden. Just make a single chip with all of the assets per movie.

My guess is their plan is to multiplex the laser. How many lasers can be reading/writing at the same time?

Multiplex the sensor?

Split the laser into 7 ish spots and read all of them at once?

That doesn’t sound that hard…