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Comment by parsimo2010 | Hacker News Reader

parsimo2010

I think this is what makes this so ridiculous. They put “room temperature” in the title and while it might not have been intentionally nefarious, it definitely has the effect that most readers assume it is about superconductors. There is nothing special about a room temperature semi conductor, your CPU, RAM, and storage drives have worked at room temperature for decades…

And if not for that word, the article would be completely unexciting. You found that you can make magnets out of multiple materials? We already knew that. If the materials aren’t abundant/cheap and easier to manufacture then this isn’t a story. And neither of those claims are tested or verified in this. So this isn’t a big deal.

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> There is nothing special about a room temperature semi conductor, your CPU, RAM, and storage drives have worked at room temperature for decades…

This is a magnetic semiconductor (and antiferromagnetic). All non-experimental magnetic semiconductors require cryogenic temperatures. If this pans out (works, cheap-ish to produce), it could mean significantly faster memory, with significantly less energy usage and significantly less waste heat (and thus, even less energy usage).

Obviously it's very far from "panning out", but "room temperature" is not a given here. It's not normal, and it would be a huge deal.

Why is it useful for semiconductors to be magnetic?

Spintronics

"Whereas traditional electronics are based on control of charge carriers (n- or p-type), practical magnetic semiconductors would also allow control of quantum spin state (up or down). "

https://en.wikipedia.org/wiki/Magnetic_semiconductor

That page lists a bunch of other stuff too.

Magnets out of multiple materials, or magnetic semiconductors at room temperature?

Wikipedia seems to say it is new, assuming this one has "robust" coexistence of the properties the framing would be important and not just thrown in there to trick people into thinking it was about superconductors:

> To date, GaMnAs remains the only semiconductor material with robust coexistence of ferromagnetism persisting up to rather high Curie temperatures around 100–200 K.

If there is an important combination of material properties that previously was only available at cryogenic temps, a room temp version is significant since you don't need cryogenic cooling to take advantage of it.

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