Semimetals are high conductors
(PHYSorg.com Physics)

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.