Sure. But how efficient are they once you include the power used to keep them cold enough to superconduct? I doubt that they're even as efficient as a normal microprocessor would be.
New superconductor microprocessor yields a substantial boost in efficiency
121–130 of 233 posts
Re: New superconductor microprocessor yields a substantial boost in efficiency
#122Earlier quoted context omitted.
Not really. You just have the whole package instead a vacuum casing.
Really. Vacuum casing is not even close to sufficient to set heat absorption to zero because of thermal radiation. And you can't just make the walls reflective once the cold object gets smaller than the wavelength of the radiation. The colder the object, the longer that wavelength.
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 helium (liquid at 4K) that you need to get to these temperatures. Your're right that thermal radiation is an issue so you have to be careful with the placement of any windows or mirrors around the device.
Souce. I have a PhD in physics where I used equipment cooled to 4K.
Re: New superconductor microprocessor yields a substantial boost in efficiency
#123Earlier 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
No need to assume when we can define ;p
Re: New superconductor microprocessor yields a substantial boost in efficiency
#124Earlier quoted context omitted.
Can't imagine why it would, but the lack of heat makes a 3D cpu much more feasible. So you could take 20 die, make 20 layers, and get radically more transistors per volume.
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.
Re: New superconductor microprocessor yields a substantial boost in efficiency
#125This microprocessor composed of some 20k Josephson junctions appears to be pure computational logic.
In practice it will need to interface to external memory in order to perform (more) useful work.
Would there be any problems fashioning memory cells out of Josephson junctions, so that the power savings can carry over to the system as a whole?
Re: New superconductor microprocessor yields a substantial boost in efficiency
#126Earlier quoted context omitted.
Really. Vacuum casing is not even close to sufficient to set heat absorption to zero because of thermal radiation. And you can't just make the walls reflective once the cold object gets smaller than the wavelength of the radiation. The colder the object, the longer that wavelength.
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.
Re: New superconductor microprocessor yields a substantial boost in efficiency
#127Earlier quoted context omitted.
This doesn't change the fact that, for any degree of heat conductivity achieved smaller packages will be hard to keep cold than large ones.
It also doesn't change the fact that smaller devices are harder to put wires on - but they're both polynomial scaling factors that other polynomial scaling paradigms could cancel out.
The topic of discussion is datacenter vs. an extremely small cryocooler. What is the other polynomial scaling paradigm that would cancel out the datacenter's advantage?
Re: New superconductor microprocessor yields a substantial boost in efficiency
#128Earlier 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
This comment took effort and adds to the discussion; what's with the downvotes?
Re: New superconductor microprocessor yields a substantial boost in efficiency
#129Earlier quoted context omitted.
If the throughput is fast enough 3+3=6 seconds latency doesn't really sound that bad. There are websites with that kind of lag. You can't use to build a chat app, but you can use it as a cloud for general computing.
Fun aside I learned about recently: we don't actually know if the speed of light is the same in all directions. So it could be 5+1=6 seconds or some other split. https://en.m.wikipedia.org/wiki/One-way_speed_of_light
There is a Veritasium video really fun to watch which exmplains with examples why you cannot measure one way speed of light: https://www.youtube.com/watch?v=pTn6Ewhb27k
Re: New superconductor microprocessor yields a substantial boost in efficiency
#130Nice, but requires 10 K temperature - not very practical. Once this can be done at the temperature of liquid nitrogen, that will be a true revolution. The difference in cost of producing liquid nitrogen and liquid helium is enormous. Alternatively, such servers could be theoretically stored in the permanently shaded craters of the lunar South Pole, but at the cost of massive ping.
I'm no physicist, but wouldn't you need some kind of medium to efficiently transfer the heat away?
On the moon you have no atmosphere to do it with radiators with fans, so I gues you would have to make huge radiators which simply emit the heat away as infrared radiation?