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New Optical Switch Up to 1000x Faster Than Transistors

spectrum.ieee.org

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

#51

Post by wnkrshm »

dogber1 wrote: post #5

In reality, all-optical computing is mostly a terrible idea: fundamentally, it cannot reach the integration density of electronics. It boils down to the elementary differences between Fermions (electrons, neutrons, etc.) and Bosons (photons, etc.). Their intrinsic behavior determines the interaction with matter, i.e. conductive/absorptive properties. As a result, optical wires (waveguides) have to be sized roughly at…

The flipside is switching speed, optically you can reach THz and more apparently, while heat/capacitance/crosstalk limit electronic transistors IIRC.

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

#52

Post by gboogie117 »

ithkuil wrote: post #43
tragictrash wrote: post #19

Earlier quoted context omitted.

This sounds to me like doctors claiming they know so much about the human body when in reality we are at the infancy of our understanding

We're in an interesting point: there is so much we don't know but in order to learn more everything we do must fit in the already immense amount of knowledge that we accumulated so far. In the vast majority of cases this requires that the people who want to nudge the frontier a bit further must first dedicate a good portion of their life's studying what we know, and as the result sounding a bit arrogant when they exp…

That’s a pretty long way around to what is essentially an appeal to authority. You’re right about the knowledge and devotion required of frontier pushers. History is full of people who challenged this thinking and completely overhauled human understanding of a topic, though, often in the face of relentless ridicule.

The error (in your telling) is equating knowledge with confidence. Knowledge is knowing you might be wrong about it all. The advice to spend one’s life questioning isn’t a smarmy nothing; it’s the only truly sensible approach when you step back and think about it.

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

#53

Post by Lichtso »

max_ wrote: post #34
kfprt wrote: post #4

If this is the transistor moment what technology would an IC equivalent require?

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 analog properties and the differential equation level of the problem away pretty much. Can't we achieve that with photonic ones as well? Or do you mean a paradigm shift in higher level things like memory bandwidth and latency vs caching etc. ?

3. When I look at the state of photonic circuits I think miniaturization and fabrication are the most obvious problems. Let's assume for a moment that these can be solved, what else makes photonic circuits worse than electric ones?

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

#54

Post by jacquesm »

dogber1 wrote: post #29
pg_bot wrote: post #13

Earlier quoted context omitted.

Isn't this just a trade off? Is there never a scenario where you would trade transistor density for switching speed and lower power consumption?

That's indeed done all the time in electronics: for example, RF CMOS usually trailing on a node three or four generations behind the bleeding edge. However, all-optical/photonic computing is just intrinsically so much worse than electronics. On top of the issues that I touched on, there are also other fundamental problems, e.g. distribution of power: photons like to get absorbed by nearby electrons. How do you then s…

There is a special case: pumped laser amplification of signal in underwater fiber optic cables. That's all optical for the signal path as far as I know.

https://www.laserfocusworld.com/fiber-optics/article/1655109...

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

#56

Post by averne_ »

dogber1 wrote: post #5

In reality, all-optical computing is mostly a terrible idea: fundamentally, it cannot reach the integration density of electronics. It boils down to the elementary differences between Fermions (electrons, neutrons, etc.) and Bosons (photons, etc.). Their intrinsic behavior determines the interaction with matter, i.e. conductive/absorptive properties. As a result, optical wires (waveguides) have to be sized roughly at…

Not true for plasmonic waveguides which can confine energy well beyond the diffraction limit. But I agree that for now, photonics is just an academic wet dream.

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

#57

Post by EVa5I7bHFq9mnYK »

dogber1 wrote: post #5

In reality, all-optical computing is mostly a terrible idea: fundamentally, it cannot reach the integration density of electronics. It boils down to the elementary differences between Fermions (electrons, neutrons, etc.) and Bosons (photons, etc.). Their intrinsic behavior determines the interaction with matter, i.e. conductive/absorptive properties. As a result, optical wires (waveguides) have to be sized roughly at…

I think fermions vs bosons is irrelevant here - you can't build transistors out of neutrons. Sure, photons at these energies are larger, but still can be used for certain tasks, like quantum computers.

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

#59

Post by jrootabega »

dogber1 wrote: post #5

In reality, all-optical computing is mostly a terrible idea: fundamentally, it cannot reach the integration density of electronics. It boils down to the elementary differences between Fermions (electrons, neutrons, etc.) and Bosons (photons, etc.). Their intrinsic behavior determines the interaction with matter, i.e. conductive/absorptive properties. As a result, optical wires (waveguides) have to be sized roughly at…

So they were right about computers the size of entire buildings, they were just off by 100 years?

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

#60

Post by McMiniBurger »

gboogie117 wrote: post #52
ithkuil wrote: post #43

Earlier quoted context omitted.

We're in an interesting point: there is so much we don't know but in order to learn more everything we do must fit in the already immense amount of knowledge that we accumulated so far. In the vast majority of cases this requires that the people who want to nudge the frontier a bit further must first dedicate a good portion of their life's studying what we know, and as the result sounding a bit arrogant when they exp…

That’s a pretty long way around to what is essentially an appeal to authority. You’re right about the knowledge and devotion required of frontier pushers. History is full of people who challenged this thinking and completely overhauled human understanding of a topic, though, often in the face of relentless ridicule. The error (in your telling) is equating knowledge with confidence. Knowledge is knowing you might be w…

> Knowledge is knowing you might be wrong about it all

that's not a great definition... I know I might be wrong about flying UFOs, but that doesn't count as 'knowledge', does it?

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