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New superconductor microprocessor yields a substantial boost in efficiency

spectrum.ieee.org

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Re: New superconductor microprocessor yields a substantial boost in efficiency

#141

Post by Calloutman »

jessriedel wrote: post #126
Calloutman wrote: post #122

Earlier quoted context omitted.

The way it works is that the entire assembly is in a vacuum. It kinda has to be as any gas which touches it will instantly condense to it or freeze to it. You then have a dual cryostat of liquid helium and liquid nitrogen cooling down the assembly (within the vacuum). The helium and nitrogen cryostat also have a vacuum shield. The nitrogen (liquid at 77K) is a sacraficial coolant which is far cheaper than liquid heli…

Great, then we both have physics PhDs, and you'll know that none of that equipment has, or easily could be, sufficiently miniaturized, which is the topic of discussion ("extremely small cryocooler"). You can't put nested closed dewers of liquid nitrogen and helium on a O(1 mm^2) microchip, and the reason is exactly what I said: it will warm up too fast.

Ah, you're totally right. I misread the OP. Sorry.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#142

Post by vincnetas »

reasonabl_human wrote: post #86
jetrink wrote: post #57

Earlier quoted context omitted.

Is it possible to do this without violating the second law of thermodynamics?

I can’t think of a reason it would violate any basic physical laws. Use a peltier cooler in reverse as the transducer from heat to electricity, apply to an appropriately spec’d solid state laser. Surely the devil is in the details somewhere..

Peltier generator would need somwhere to transfer the heat to. But there is nothing around.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#143

Post by fastball »

gibbonsrcool wrote: post #124
fastball wrote: post #51

Earlier quoted context omitted.

Seems like it would be much harder to keep a stacked CPU superconducting as heat dissipation would be more difficult.

Maybe I'm misunderstanding but since this 3D CPU would be superconducting, it would conduct electricity without resistance and therefore not generate any heat while in use.

The adiabatic (reversible) computations themselves would be zero-loss, but in order to actually read the result of your computation you need to waste heat.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#144

Post by jessriedel »

Calloutman wrote: post #141
jessriedel wrote: post #126

Earlier quoted context omitted.

Great, then we both have physics PhDs, and you'll know that none of that equipment has, or easily could be, sufficiently miniaturized, which is the topic of discussion ("extremely small cryocooler"). You can't put nested closed dewers of liquid nitrogen and helium on a O(1 mm^2) microchip, and the reason is exactly what I said: it will warm up too fast.

Ah, you're totally right. I misread the OP. Sorry.

No problem :)

Re: New superconductor microprocessor yields a substantial boost in efficiency

#145

Post by fastball »

cbozeman wrote: post #52
vincnetas wrote: post #34

Earlier quoted context omitted.

Its a bit cold in space. But actually its really difficult to cool down things in space as there is nothing around you to transfer heat to.

Mass Effect taught me this. I miss old school BioWare.

Was this a plot point in ME? I don't remember that.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#146

Post by jessriedel »

extropy wrote: post #136
jessriedel wrote: post #126

Earlier quoted context omitted.

Great, then we both have physics PhDs, and you'll know that none of that equipment has, or easily could be, sufficiently miniaturized, which is the topic of discussion ("extremely small cryocooler"). You can't put nested closed dewers of liquid nitrogen and helium on a O(1 mm^2) microchip, and the reason is exactly what I said: it will warm up too fast.

What's wrong with attaching said microchip to a piece of copper for increased size? Genuinely curious. To be useful in a data center you could cool a slab of copper the size of a fridge and surface mount thousands of chips on it.

The topic is cooling small objects so that personal electronics (e.g., your phone) can compete with datacenters. Cold at scale (i.e., in datacenters) is comparatively easy.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#147

Post by dcposch »

the8472 wrote: post #18

> We use a logic primitive called the adiabatic quantum-flux-parametron (AQFP), which has a switching energy of 1.4 zJ per JJ when driven by a four-phase 5-GHz sinusoidal ac-clockat 4.2 K. The landauer limit at 4.2K is 4.019×10^-23 J (joules). So this is only a factor of 38x away from the landauer limit.

> adiabatic quantum-flux-parametron

https://youtube.com/watch?v=BBqIlBs51M8

Re: New superconductor microprocessor yields a substantial boost in efficiency

#148

Post by rbanffy »

yazaddaruvala wrote: post #118
ajuc wrote: post #105

Earlier quoted context omitted.

> IMO, The fact that it's only 38x the minimum is MIND BLOWING. It's like if someone made a car that drives at 1/38th the light speed.

For anyone too lazy to math, its a car that can go: 28.4 million km per hour (i.e. 17.6 million miles per hour) I wonder how much that speeding ticket would cost. Disclaimer: Assuming the one-way speed of light is 300k km/s

> I wonder how much that speeding ticket would cost.

I once got one for going at about 3x the speed limit (very nice road in Brazil, broad daylight, nobody in sight, short run, and very unfortunate radar gun positioning). The policeman was impressed and joked that he would like to, but couldn't give me 3 speeding tickets instead of one.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#149

Post by cbozeman »

fastball wrote: post #145
cbozeman wrote: post #52

Earlier quoted context omitted.

Mass Effect taught me this. I miss old school BioWare.

Was this a plot point in ME? I don't remember that.

It was one of the "scan a planet" type side mission things.

I just remember that that particular planet didn't have much of an atmosphere, so it wasn't good for dumping excess heat from ships.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#150

Post by cbozeman »

f1refly wrote: post #116
cbozeman wrote: post #49

Earlier quoted context omitted.

Dumb terminals everywhere. A huge upgrade of high-speed infrastructure across the US since everyone will need high throughput and low latency. Subscriptions will arise first, as people fucking love predictable monthly revenue - and by people I mean vulture capitalists, and to a lesser degree, risk-averse entrepreneurs (which is almost an oxymoron...), both of whom you can see I hold in low regard. Get ready for a "$3…

I really appreciate your pessimistic worldview, keep it up!

I basically just base my worldview on the fact that everyone is ultimately self-serving and selfish. Hasn't failed me yet. :)
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