Solid State Cryocooling?

A

Axewerfer

Limp Gawd
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Dec 1, 2006
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Is anyone here familiar with the concept of a solid state crocooler? It's an extreme low-temperature device typically run from liquid nitrogen/helium. They operate on different principles from what I can tell. Some are designed as stirling engines, the more recent are pulse tube crocoolers, which have even fewer moving parts.I'm not too familiar with the theory, but I've seen them advertised at temperatures of around 1.4K (-457.15ºF/-271.75ºC). They're big, bulky, probably cost a small fortune, and have that nasty issue of needing a constant supply of volatile cryogenic liquid, but past that, it seems to me it would push the idea of extreme cooling into overkill. Better yet, most of them that I've seen appear to focus the temperature on a single component called a Coldtip Thermal Interface. Aside from the chipset probably shattering from the cold, what's the consensus on these?

Some links:

http://www.janis.com/p-ssptc.html
http://www.eng.ox.ac.uk/cryogenics/
http://www2.jpl.nasa.gov/adv_tech/coolers/summary.htm
 
The main issue is once you get a semiconductor too cold it just becomes a large resistor and stops functioning properly.
 
I see, so there is such a thing as too much of a good thing? Any idea what the cutoff is? And if, theoretically, a semiconductor were chilled to absolute zero would it then behave as a superconductor, or does that require a differet material composition?
 
With base temperatures of 45 K or 55 K, and a cooling power of 10 W at
77 K or 5 W at 80 K, these new refrigerators are ideal for applications where low vibration levels are critical, including detector cooling.
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if 10 W means 10 Watts, this isnt going to work too great on a 180 watt processor. i think these are designed to go hold super low temps on components that do not produce much heat. the opposide of a C2D, which produces more watts of heat per square inch then any other electronic component in the world.

also at absoloute zero a semiconducter acts as an insulator so if we were able to get that low, processors would have to be entirely redesigned using another material.
 
ghost6303 said:
if 10 W means 10 Watts, this isnt going to work too great on a 180 watt processor. i think these are designed to go hold super low temps on components that do not produce much heat. the opposide of a C2D, which produces more watts of heat per square inch then any other electronic component in the world.
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I think that Prescott, Cedar Mill, Smithfield and Presler may be worse in terms of heat per given surface area.
 
mavalpha said:
I think that Prescott, Cedar Mill, Smithfield and Presler may be worse in terms of heat per given surface area.
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those dies have larger surface area if im not mistaken.

and these do not get down to absoloute zero, its impossible (at present) to get that far down, although we have come close with stuff like liquid helium.
 
ghost6303 said:
if 10 W means 10 Watts, this isnt going to work too great on a 180 watt processor. i think these are designed to go hold super low temps on components that do not produce much heat. the opposide of a C2D, which produces more watts of heat per square inch then any other electronic component in the world.

also at absoloute zero a semiconducter acts as an insulator so if we were able to get that low, processors would have to be entirely redesigned using another material.
Click to expand...

Perhaps you are not too familiar with intel's last two generations of chips.
C2D runs cooler, then the past few.
 
OK, I see where the issue comes in. I missed the Watts first go around. It does raise the question of whether something like this could be designed to run at a proportionately higher temperature and draw off greater wattage (am I using that word properly?). There are definately some benefits to the technology that I can see, since they've made these things to function for ten years at a stretch without maintenance in space. Doesn't really fix the issue with size, but an entertaining notion...

P.S. And according to the current laws of thermodynamics, absolute zero is unattainable. You can get asymptomatically close, but the concept of zero-point energy means there will always be a certain degree of molecular motion within a system. Courtesy of some quick research, but I've taken enough Chem I ought to be able to tell if that has a basis in fact, and the third law of thermodynamics is pretty easily looked up...
 
Axewerfer said:
I see, so there is such a thing as too much of a good thing? Any idea what the cutoff is? And if, theoretically, a semiconductor were chilled to absolute zero would it then behave as a superconductor, or does that require a differet material composition?
Click to expand...

The point at which the semiconductor loses donors depends on its doping. As for superconductivity, most conductors become insulators at very low temperatures while superconductors start as insulators at room temperature and superconduct at the low temperatures.
 
At absolute zero there is NO subatomic movement, thus no electron flow thus no electric current, the only form of energy that remains in that temperature is Zero Point Energy. If something achieves that temperature it will no longer be a solid nor a liquid nor gas nor plasma, it´ll be something else a colloidal substance of some sort according to one of Einstein´s theories.
 
Wrong. At absolute zero molecular motion stops. Electrons continue to move. Read about the Heisenberg uncertainty principle.
 
There were some experiments a while back where a gaseous cluster of Rubidium atoms was chilled to extreme temperatures and turned into a state of matter called a Bose-Einstein Condensate, is that what you're thinking of? It's cool stuff, breaks all the normal rules and exhibits superfluidity and whatnot. If you had enough of it, it would climb the walls of any container you put it in. How did we get into this discussion again?
 
breaks all the normal rules and exhibits superfluidity and whatnot. If you had enough of it, it would climb the walls of any container you put it in. How did we get into this discussion again?
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Cause we all like physics apparently, and I used to (a long time ago in a galaxy far.... ) exhibit the same properties with a quart of Jack Daniels and a joint.
 
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