New Optical Switch Up to 1000x Faster Than Transistors • Hacker News Board

Re: New Optical Switch Up to 1000x Faster Than Transistors

#91

Post by max_ » Wed, Oct 20, 2021, 5:51 PM UTC

Lichtso wrote: post #53

max_ wrote: post #34

Earlier quoted context omitted.

First we need a new paradigm of computing that is consistent with how light behaves.

Some questions from someone who is simply interested in the topic and seeks to expand their understanding. 1. For electrical circuits we are interested in properties like resistance, capacity, inductance etc. for passive elements and in the characteristic curves for active ones. What are their equivalents in photonic circuits? Which properties matter here? 2. In digital computing I think we abstracted the electrical…

Unfortunately I am no expert. Most of these questions go beyond my knowledge.

But you should definitely watch this video [0].

[0]: https://youtu.be/EwueqdgIvq4

Re: New Optical Switch Up to 1000x Faster Than Transistors

#92

Post by neltnerb » Wed, Oct 20, 2021, 5:57 PM UTC

rocqua wrote: post #49

neltnerb wrote: post #11

Earlier quoted context omitted.

These sound a lot like room temperature optical qubits... I'm certain I am missing something but this sounds pretty neat.

They probably aren't in a superposition, let alone entangled with each other.

Gotcha, if I am reading this right the mechanism for the switch is quantum but the property is not. So no different in that regard than in semiconductors where the underlying behavior is due to quantum mechanics but the actual computing elements are functioning like analog non-linear elements.

Thanks!

Re: New Optical Switch Up to 1000x Faster Than Transistors

#93

Post by dTal » Wed, Oct 20, 2021, 8:41 PM UTC

tremon wrote: post #84

BenjiWiebe wrote: post #81

Earlier quoted context omitted.

Perhaps I'm misunderstanding your comment, but the frequency doesn't change the speed of light.

They're talking about wavelengths ("per cycle"). But I'm not sure it makes more sense knowing that, since there's a fundamental disconnect between the signal frequency and the carrier frequency. I think QAM can even be used on a signal rate that's higher than the carrier frequency (as long as the carrier frequency is known), but I'm not 100% sure.

If we take our definition of "individual computing module" to be that it has a defined state during every tick of the clock, then there is a hard physical limit of 30cm for a module that runs at 10ghz. Anything larger must be operating asynchronously, as a distributed system.

Re: New Optical Switch Up to 1000x Faster Than Transistors

#94

Post by lostmsu » Wed, Oct 20, 2021, 10:25 PM UTC

coldtea wrote: post #74

Veedrac wrote: post #71

Earlier quoted context omitted.

> all-optical computing The keyword here is ‘all’. There are some things optical computing is bad at. However there are some things it is unparalleled at. For example, light can multiplex. It can have much lower energy losses. It can run at much higher frequencies. It is by far the best way to transmit information at extremely high data rates. Even within a chip, free space optical communication has massive theoretic…

But the whole wisdom of the parent comment is in the last sentence. This is mostly what is happening with such papers. The keyword here might be "all", and there are some applications where optical computing is unparalled at. But research teams, vendors, and the media spin those things are a recplament for every application, not as some niche thing that's good at some niche applications that most people need not care…

To me it sounds like the counterargument nulls the wisdom. If you can only make 200nm optical nodes, but they could multiplex 1M signals, you'd win by 100x over 2nm electrical nodes. It will be 100_000x if you add 10THz vs 10GHz difference to the picture.