The American energy physicists of the Ames laboratory investigated the so-called topological metals, in particular PtSn4 (platinum and tin). It has been found that they have a unique electronic structure that could one day lead to efficient energy savings for computers while increasing processor speed and access to data storage.
Electrons in topological quantum materials can travel at speeds close to the speed of light due to the unique properties of Dirac dispersion. In a huge variety of materials studied, only individual groups of electrons located near the so-called Dirac point were identified. But in PtSn4, scientists not only detected a high density of conduction electrons, but also found a large number of closely spaced Dirac points, forming extended lines or nodes of Dirac arcs.
"This mode of electron transport is highly specific," said Adam Kaminski, a scientist and professor in the Department of Physics and Astronomy at Iowa State University. "In our research, we managed to connect the extreme values of magnetoresistance with innovations in electronic structure, which may lead in the future to an increase in the speed of computers, efficiency in storing information."
The discovery was made with a laser angular photoemission spectroscope assembled in Ames's laboratory specifically for Kaminski. The device provides high-resolution measurements of electronic material properties details.