A typical integrated circuit pushes electrical voltage across pathways, with transistors and stuff modifying it. When you interpret those voltages as mathematical values and logical instructions, then congratulations, you have created a processor, memory, and so forth. You don't need to use electricity for this. In fact, the history of Charles Babbage and Ada Lovelace was their attempts to perform computation on mechanical state.
Image Credit: University of Colorado
Chip contains optical (left) and electric (top and right) circuits.
One possible follow-up is photonic integrated circuits. This routes light through optical waveguides, rather than typical electric traces. The prototype made by University of Colorado Boulder (and UC Berkeley) seem to use photonics just to communicate, and an electrical IC for the computation. The advantage is high bandwidth, high density, and low power.
This sort of technology was being investigated for several years. My undergraduate thesis for Physics involved computing light transfer through defects in a photonic crystal, using it to create 2D waveguides. With all the talk of silicon fabrication coming to its limits, as 14nm transistors are typically made of around two-dozen atoms, this could be a new direction to innovate.
And honestly, wouldn't you want to overclock your PC to 400+ THz? Make it go plaid for ludicrous speed. (Yes, this paragraph is a joke.)
Very exciting. Futuristic…
Very exciting. Futuristic…
Overclocking light? Count me
Overclocking light? Count me in. (It’s a joke)
Well you could “overclock
Well you could "overclock light" by giving it blue-shift (decrease wavelength). The joke is because it's a false-equivalence. A processor using red light won't behave like an electric CPU at 400 THz. It's probably impossible to switch state within a single cycle of light.
Also, mixing red and green light to make your circuit "go plaid" is definitely a joke, too.
Considering that maybe the
Considering that maybe the light channels can carry more than one wavelength, and that photons generate a lot less heat than electrons this is great news. Now systems could be made on an interposer with the interposer having light waveguides instead of only electrical traces that would be able to via light have much more bandwidth, and just imagine a GPU with light based waveguides to each of its compute engines and the its execution units able to have enough bandwidth to never be stalled waiting for data. If anything having just the buses becoming light based on CPUs/GPUs/other processing devices will definitely reduce the amount of heat generated while allowing for possible Multi-terabyte per second data transfers to and from the processing cores, but also optical fiber connections off die to memory and off motherboard to and from peripheral devices as well.
Yeah, the paper discussed
Yeah, the paper discussed multiplexing. It should also be much easier to develop 3D circuits, too. Shouldn't be much heat generated, and routing up is no different from routing horizontally.