Materials

New superconductivity record edges closer to room temperature

New superconductivity record e...
A team used a pressure chamber, which squeezes samples to 1.7 million times atmospheric pressure, to make lanthanum hydride, which was found to remain superconductive at -23° C
A team used a pressure chamber, which squeezes samples to 1.7 million times atmospheric pressure, to make lanthanum hydride, which was found to remain superconductive at -23° C
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A team used a pressure chamber, which squeezes samples to 1.7 million times atmospheric pressure, to make lanthanum hydride, which was found to remain superconductive at -23° C
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A team used a pressure chamber, which squeezes samples to 1.7 million times atmospheric pressure, to make lanthanum hydride, which was found to remain superconductive at -23° C

No matter how good a material is at conducting electricity, there's usually some resistance – unless you use superconductive materials. Since they can conduct electricity with absolutely no loss, they could be revolutionary if not for one little problem: they only work if kept extremely cold. But now researchers at Max Planck have reported a new record high temperature for superconductivity, at a toasty -23° C (-9.4° F).

Normally, when electrons are flowing through a conductor their negative charge means they repel each other, sending them bouncing off nearby atoms. That in turn wastes a decent chunk of their energy, and we can feel this unwanted side effect as the heat given off by electronic devices.

But that doesn't alway have to be the case. Superconductors keep electrons flowing with no resistance at all, which can go a long way towards improving electrical circuits and storage – for example, a loop of superconducting wire can keep an electrical current flowing indefinitely, with no need for a power source.

Unfortunately, for now superconductors need to be chilled to extremely low temperatures to work – usually below -234º C (-389º F), which all but rules them out for most practical uses. Ideally they would work at room temperature, but the best attempts so far have only gotten them to -70° C (-94° F).

The new study, by the same researchers as the previous record, has now managed to warm superconductors up to -23° C, which is a huge leap towards room temperature. To do so, the team placed metallic lanthanum and hydrogen gas into a pressure chamber and squeezed the samples intensely – up to 1.7 million times stronger than regular atmospheric pressure. That creates a material called lanthanum hydride (LaH10).

Next, the researchers cooled the material down, and found that at the relatively high temperature of -23° C, the electrical resistance dropped to zero. This finding was backed up by measurements taken in an external magnetic field.

"Our study is a major step and milestone on the road to superconductivity at room temperature," says Eremets, lead researcher on the study.

The next steps for the team are to experiment with other materials such as yttrium hydride, which may allow superconductivity at even higher temperatures.

The research was published in the journal Nature.

Source: Max Planck

6 comments
Malatrope
This is nice, but there is another aspect of superconductive materials that has a larger impact than temperature: their resistance suddenly comes back if the magnetic field strength gets too high. Thus, they cannot be made into power conductors because the current within them creates a field large enough to crash them out of their superconductive state. This level is called, simply enough, the "critical magnetic field level". It varies with material.
Kpar
I have been waiting for news on high-temp superconductors. Thanks. Here's hoping that there will be news on Thorium molten salt reactors, soon.
guzmanchinky
The implications for this are world changing.
Gregg Eshelman
Room temperature superconductors will be nothing but a curiosity until they can be made into wires, at least for the main high power distribution lines. When they can be made into replacements for wiring in buildings, that will be revolutionary. Same for if superconducting motors can be built. That would dramatically increase the range of electric vehicles, or provide the same range from much smaller batteries. 'Course we know which way the vehicle industry would go, smaller batteries. Same thing they usually do with gasoline powered vehicles that are more efficient, put smaller fuel tanks in so they still need to be gassed up as often. What good does it do for a moped or scooter to get 100 MPG if it has a literally pint sized fuel tank?
MarkGoldes
There are a number of room temperature superconductors. None are yet recognized by the scientific mainstream. See a few under that heading at aesopinstitute.org Many more at superconductors.org
paul314
That temperature is nice, but if you have to keep it under diamond-anvil pressure that's still not terribly useful. Even though power transmission is still really difficult for superconductors (there is some good work on cables) there are probably some sensor and computing applications that would benefit from superconductors that don't need fancy cooling.