Supercomputers without waste heat
A collaboration at the University of Konstanz between the experimental physics group led by Professor Elke Scheer and the theoretical physics group led by Professor Wolfgang Belzig uses an approach based on dissipation-free charge transport in superconducting building blocks. Magnetic materials are often used for information storage. Magnetically encoded information can, in principle, also be transported without heat production by using the magnetic properties of electrons, the electron spin. Combining the lossless charge transport of superconductivity with the electronic transport of magnetic information -- i.e. "spintronics" -- paves the way for fundamentally novel functionalities for future energy-efficient information technologies.
The University of Konstanz researchers address a major challenge associated with this approach: the fact that in conventional superconductors the current is carried by pairs of electrons with opposite magnetic moments. These pairs are therefore nonmagnetic and cannot carry magnetic information. The magnetic state, by contrast, is formed by magnetic moments that are aligned in parallel to each other, thereby suppressing superconducting current.
"The combination of superconductivity, which operates without heat generation, with spintronics, transferring magnetic information, does not contradict any fundamental physical concepts, but just naïve assumptions about the nature of materials," Elke Scheer says. Recent findings suggest that by bringing superconductors into contact with special magnetic materials, electrons with parallel spins can be bound to pairs carrying the supercurrent over longer distances through magnets. This concept may enable novel electronic devices with revolutionary properties.
[...] "It is important to find materials that enable such aligned electron pairs. Ours is therefore not only a physics but also a materials science project," Elke Scheer remarks. Researchers from the Karlsruhe Institute of Technology (KIT) provided the tailor-made samples consisting of aluminium and europiumsulfide. Aluminium is a very well investigated superconductor, enabling a quantitative comparison between theory and experiment. Europiumsulfide is a ferromagnetic insulator, an important material property for the realisation of the theoretical concept, which maintains its magnetic properties even in very thin layers of only a few nanometres in thickness as used here. Using a scanning tunnelling microscope developed at the University of Konstanz, spatially and energetically resolved measurements of the charge transport of the aluminium-europiumsulfide samples were performed at low temperatures. Contrary to commercial instruments, the scanning tunnelling microscope based at the Scheer lab has been optimized for ultimate energy resolution and for operation in varying magnetic fields.
Journal Reference:
S. Diesch, P. Machon, M. Wolz, C. Sürgers, D. Beckmann, W. Belzig, E. Scheer. Creation of equal-spin triplet superconductivity at the Al/EuS interface. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-07597-w
(Score: -1, Offtopic) by Anonymous Coward on Tuesday December 11 2018, @01:31AM
The man nervously got up in front of the podium. Once he noticed the audience's warm, caring gaze, the man calmed down and smiled. That's right: This was a Human Rights Convention where those who have less common sexual preferences could come out and be accepted for who they are. This place was a testament to the fact that society decided to stand against bigotry and injustice! The man began speaking.
"Hello, everyone. My name is Jackson. My favorites are little girls around the age of 9. I enjoy raping them until they're silent and then killing them. My favorite part about it is when they lose all hope and become shells of what they once were." the man said.
Courage. The man had immense courage to be able to say that. But what would the audience think? The man became nervous again.
Cheering. Clapping. Standing. A standing ovation! The audience was enamored by the man's courage and would stand behind him at all costs. No one here would allow bigots to threaten the man's freedoms. And while a few such bigots were protesting in the audience, fists rained down upon them until their faces collapsed; they were no longer bigots, but embodiments of silence.
A single tear ran down the speaker's face. Support. Such immense support would allow the man to freely express his sexuality for the rest of his life. Finally, the man could feel safe from those who might wish to oppress him. True happiness.
(Score: 2) by hendrikboom on Tuesday December 11 2018, @02:11AM (3 children)
There's a point where it is the physics itself rather than technological limitations that force heat production during computation. That is when information is destroyed. Each bit of destroyed information corresponds to an amount of heat production.
(Score: 0) by Anonymous Coward on Tuesday December 11 2018, @03:13AM (1 child)
Nothing that cant be overcome using clever engineering.
(Score: 2) by hendrikboom on Tuesday December 11 2018, @02:52PM
For example, designing computations that are completely reversible so that no bit of information is ever destroyed. This might be quantum computation -- until the moment you observe the output of the computation.
(Score: 2) by MichaelDavidCrawford on Tuesday December 11 2018, @05:39AM
I never read their actual paper but they concluded that while the energy required to compute could be made very small it was nonzero
A while back I was looking into conserving energy by refactoring source. No one at kuro5hin believed it was even possible, to which I replied "Why do you need to plug in your box?"
Yes I Have No Bananas. [gofundme.com]
(Score: 2) by MostCynical on Tuesday December 11 2018, @02:41AM (3 children)
is there any movement, even at the microscopic level?
If so, there will be heat.
If there is no movement, how is the infomation encoded?
"I guess once you start doubting, there's no end to it." -Batou, Ghost in the Shell: Stand Alone Complex
(Score: 2) by Runaway1956 on Tuesday December 11 2018, @03:47AM (1 child)
Microscopic level? Since TFS/TFA is about electrons, then you're talking about an electron microscope to see any movement. We may need to parse words, and establish some definitions, but yes, it seems there is some movement, which will generate some amount of heat. Maybe TFA should be more clear that they've reduced the amount of waste heat, rather than eliminated waste heat altogether. Maybe they've reduced waste heat by an order of magnitude, or more, but there will probably still be waste heat.
(Score: 0) by Anonymous Coward on Tuesday December 11 2018, @04:20AM
https://helix.northwestern.edu/article/superpowers-superconductors [northwestern.edu]
(Score: 2) by hendrikboom on Tuesday December 11 2018, @02:39PM
The amount of energy involved in a bit of information depends on the ambient temperature, and is greater at higher temperatures. After all, a 'bit' is a unit of entropy.
I once saw a calculation that there were ultimate limits on computation speed because the mass-energy involved in the information would reach the density needed for gravitational collapse of the entire computing system into a black hole.
Silly, I thought. Can't we just compute using black hole dynamics?
(Score: 2) by The Mighty Buzzard on Tuesday December 11 2018, @04:16AM (5 children)
How about you just move the heat produced away and put it to productive use? I know it's fun to figure out new ways to do things you thought were impossible but that's also the difference between a scientist and an engineer. The former thinks pie in the sky thoughts for the sheer sake of thinking them, the latter has a damned job to do and saves their likely pointless speculative thinking as a hobby for off hours.
My rights don't end where your fear begins.
(Score: 2) by MichaelDavidCrawford on Tuesday December 11 2018, @05:43AM (4 children)
My office buildings management shuts off the heat on weekends. Already I have to wear my beanie when I'm there.
They also specifically forbid space heaters so I'm just going to bring my Xeon box to work. Problem Solved.
Yes I Have No Bananas. [gofundme.com]
(Score: 2) by The Mighty Buzzard on Tuesday December 11 2018, @10:57AM (3 children)
Or you could use the unheated building as a place to dump heat from the server room, thus saving on conditioning the air of both areas.
My rights don't end where your fear begins.
(Score: 2) by MichaelDavidCrawford on Tuesday December 11 2018, @11:21AM (1 child)
There's a whole data center upstairs. My office has a door to the outside, for access to the fire escape stairway. Or perhaps I can somehow get the building management to give permission for me to bore a hole in my ceiling.
There's a really easy way to do that, but I'd have to go upstairs then bore down: use a gadget called a biscuit cutter, a notched cylinder open on just one end, bolted to a drill in a puddle of coarse abrasize surrounded by a putty dam.
I'm not able to find a decent link with a photo of a biscuit cutter, but I _will_ say that for both the telescope mirrors I drilled, I employed Campbell's Condensed Soup cans so as to ensure I'd always have ready access to the correct sized tube.
Yes I Have No Bananas. [gofundme.com]
(Score: 3, Insightful) by The Mighty Buzzard on Tuesday December 11 2018, @03:48PM
They're the ones having to pay to dump waste heat outside. Let them figure it out.
My rights don't end where your fear begins.
(Score: 2) by JoeMerchant on Tuesday December 11 2018, @01:45PM
Now you're thinking, that's not allowed here (here being the corporate office building.)
Please direct your innovative ideas to the innovative ideas bin, ahem, evaluation center for further consideration.
🌻🌻 [google.com]
(Score: -1, Troll) by Anonymous Coward on Tuesday December 11 2018, @10:17AM (2 children)
you've already failed.
(Score: 2) by hendrikboom on Tuesday December 11 2018, @02:50PM (1 child)
Might work in space?
(Score: 2) by The Mighty Buzzard on Tuesday December 11 2018, @03:49PM
I envision a guy in tights and a cape waving a stick up in front of an orchestra.
My rights don't end where your fear begins.