Semimetals are high conductors

Phys.org ^ | March 18, 2019 by | Andy Fell, UC Davis

[BenLurkin]

Researchers in China and at UC Davis have measured high conductivity in very thin layers of niobium arsenide, a type of material called a Weyl semimetal. The material has about three times the conductivity of copper at room temperature, said Sergey Savrasov, professor of physics at UC Davis. Savrasov is a coauthor on the paper published March 18 in Nature Materials.

The Chinese team were able to fabricate and test small pieces, called nanobelts, of niobium arsenide, confirming the predictions of theory. The nanobelts are so thin they are essentially two-dimensional.

If you think of electrons flowing through material, imagine them bouncing off or scattering from impurities. At the quantum level, a conductive material has a Fermi surface which describes all the quantum energy states that electrons can occupy. This Fermi surface affects conductivity of the material.

The nanobelts tested in these experiments had a limited Fermi surface or Fermi arc, meaning that electrons could only be scattered to a limited range of quantum states.

Materials that are highly conductive at very small scales could be useful as engineers strive to build smaller and smaller circuits. Less electrical resistance means that less heat is generated as current passes through

[NorthMountain]

Materials that are highly conductive at very small scales could be useful as engineers strive to build smaller and smaller circuits. Less electrical resistance means that less heat is generated as current passes through

I read the article ...

[Tucker39]

Funny. I had one of those beanies as a kid. The problem with it was that I had to run and supply the wind to make it spin. As I said previously, I might consider a small solar panel hung on my beach umbrella to keep my phone and tablet charged while listening to El Rushbo. Blessings on your weekend.

[between_the_lines_mn]

better wires on a chip won’t help power consumption. The first contributor to chip power is switching power. Its the power is used every time you switch a net and most of the power is consumed in the transistors. High end CPUS run from 3 Ghz to 5 Ghz. That’s 5,000,000,000 switches per second.

the second contributor to power is leakage current. The insulators are getting so thin, they also conduct measurable amounts of current. One of the manufacturing tests is to power up the chip and measure this current. If the number is too high, the part is discarded.