On: Room-Temperature Superconductivity Achieved for th...

[HarryHirsch]

It is a diamond press, the diamonds have to be cut to shape and they also have to be transparent. Industrial diamonds aren't transparent enough.

[Sharlin → HarryHirsch]

Modern lab-grown diamonds are higher quality than even the finest gem-quality natural diamonds.

[kulahan → Sharlin]

From what I understand, the issue with lab-grown diamonds is that they can't really grow them beyond a certain size at this time. I think clear ones are a couple of carats, and colored ones are roughly double that. I could be off a bit. Regardless, that's not huge, though I don't know what size they require. Maybe it's sufficient.

[gautamcgoel → HarryHirsch]

Why do the diamonds need to be transparent?

[HarryHirsch → gautamcgoel]

People interested in high-pressure chemistry follow what's happening with spectroscopy, UV/Vis or infrared. Fig. 3 on p. 376 has the Raman spectrum.

[TheAdamist → gautamcgoel]

So they can probe/measure the contents with light, usually in laser form.

Contents are completely enclosed by diamond to hold the pressure. No way to probe otherwise as far as i know.

[s0rce → TheAdamist]

X-rays are also widely used to probe high pressure matter within diamond anvil cells

Here is an example at an ESRF beamline https://www.esrf.eu/home/UsersAndScience/Experiments/MEx/ID1...

[smartscience → s0rce]

Don't forget neutrons! Not as quick to measure, and not so good with very small samples, but well-suited to combinations of extreme environments beyond just pressure, such as temperature, magnetic field, voltage gradient etc. https://www.isis.stfc.ac.uk/Pages/Pearl.aspx

[HarryHirsch → smartscience]

Amusing to see for an x-ray crystallographer that the neutron scattering coefficient for tungsten carbide is actually lower than for pure carbon. Neutrons are weird.