Optical computing

Photonics:
http://news.berkeley.edu/2015/12/23/electronic-photonic-microprocessor-chip/

http://www.nextbigfuture.com/2008/01/3d-waveguide-is-promising-for-optical.html

https://en.wikipedia.org/wiki/Optical_computing

Summary:
Photonics is a way to make computers using light instead of electricity. According to some scientists, it could be many times faster then traditional electronics. The basic component of photonics is, like electronics, the optical transistor, which is used to make optical logic gates, which are combined to make optical chips.

I think that it's a cool idea, and I wonder if it would be possible to use sunlight to power an optical computer. If it is, then we could have computers that never need recharging, which would be perfect for people in developing countries and remote places.

I also wonder if it would be possible to make an optical battery.