A material discovered by scientists at Princeton University could become a factor in future electronic technology.

The material was made with layers of tantalum and arsenic, creating a Weyl semi-metal. It acts simultaneously like a metal, conducting electrons, and like an insulator, blocking them. The researchers say that electrons sink into the material, like going down a “rabbit hole,” and appear on the opposite surface. This behavior, the researchers say, is unlike the majority of materials where electrons float to the top. In this instance, the electrons sink into the crystal through special conductive channels.

Scanning tunneling microscopy reveals electrons on the surface of Weyl semi-metals. Image source: Yazdani et al., PrincetonAli Yazdani, member of the research team says, “You don’t find anything else like this in other materials.”

In trying to understand the material's unique properties, initial results suggest electrons plunge through the crystal when travelling at the Wyel momentum (a specific speed and direction). The electrons in these crystals hit Weyl points (special values of momentum), that move them from the top surface to its opposite. Additionally, while most electrons move in a wave or ripple-effect pattern, the Weyl semi-metals only create half circles, which has inspired the name “Fermi arcs.” They were able to observe the patterns of the electron flow using a scanning tunneling microscope, and were puzzled by the missing interface patterns they anticipated viewing. The researchers say that the strange behavior of the electrons is due to topological connections throughout the material.