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Comment by ggm | Hacker News Reader

The important thing with any superconducting discovery is the operating temperature and pressure.

In a historic achievement, University of Rochester researchers have created a superconducting material at both a temperature and pressure low enough for practical applications.

20 ℃ and 10 kilobars pressure.

The temp, I like. the pressure, I don't see how this is practical in engineering deployment. I'd trade some of that heat to get less pressure at this point, contrary to normal "warmer is better" -so what reduction in pressure for what degrees C of cooler temp?

(not an engineer or materials physics person)

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Bulk metals could get into the vicinity of the pressure requirements, but I suppose first applications would be e.g. microwave components that can be fabricated small enough to fit into a diamond anvil cell (think e.g. of lossless inductors or Josephson junctions for high-frequency components). Also, cooling the material might reduce the required pressure significantly, and cooling to e.g. -100 °C is not very expensive and can be done with semiconductor components, so having a superconductor in that range should already open many applications. That said there are some cuprate superconductors that come close to that temperature range already (without needing pressurization) and they still haven't been commercialized widely as the fabrication process is quite involved (e.g. chemical vapor deposition of single atomic layers) and the resulting material (a ceramic) is extremely brittle, so it wouldn't survive long in most environments where semiconductors are used e.g. due to vibration. So whether this will be a commercial success also depends on the material properties. Lutetium hydride has probably better properties than cuprate semiconductors already, but again proving superconductivity is only the beginning, it can be a long way before this becomes commercially viable (if that happens at all).

Materials can be pressurized in other materials. Like a soda can. Curious to see what materials can easily handle maintaining 10 kilobars of pressure.

ChatGPT says Titanium, Tungsten, and Stainless Steel can handle above 10k. Even carbon fiber can. Imagine a tiny resistor-like component where inside is pressurized superconductor. Like a tiny capacitor.

Please don't quote ChatGPT answers, they sound very believable, but often have no basis in reality.

Material stress doesn't work like a soda can. Epitaxial thin films are stressed by an underlying lattice, for example, not by being squeezed in some container. These stresses can be very high (although i don't know the order of magnitude off the top of my head)

Imagine dropping your phone and instead of the screen cracking, the chassis blasts apart. Pressurising materials using other solids doesn’t disappear the energy needed to maintain the pressure.

Funny you mention glass cracking because tempered glass has the same kind of internal pressure. Safety glass on a car has nearly a kilobar. It breaks up without blasting apart.

Pressure != Energy. If it's a very stiff (aka brittle) material, then it doesn't deform enough to actually contain much energy even at high pressure.

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