Is it possible to build RAM and SSDs in optical circuits yet? I ask because this has very interesting military uses that could push this forward if you could have devices impervious to electro-magnetic pulses.
What we do with photonics is to improve areas where the electronics is not efficient.
Case and point: interconnections. If you want to move data from point A to point B (being A and B either two different chips in your board our two datacenters), we can do it using electric signals, it works just fine, but at some cost. Electric signals dissipate power when they travel through a conductor, no matter how good the conductor is.
If instead we use optical signals instead of electrical, we have advantage in a number of points, specially power efficiency.