General theory of relativity makes its debut in material physics
Einstein's general theory of relativity predicts that light will be scattered by gravity, even though it has no mass. That is because the space is curved by gravity. As a result of this scattering a star sometimes functions as a lens, a so-called gravitational lens. FOM researchers at Leiden University have now discovered that the consequences of the general theory of relativity can be simulated in certain materials. They have demonstrated that electrons in bismuth crystals move as if the space is curved.
Bismuth crystals are so-called topological insulators. They have the unusual property that electrons move over the surface as if they were light particles, without any mass. A bump on the surface has exactly the same effect as a curve in space, and therefore functions as a lens for the electrons as well (see image).
Einstein's special theory of relativity had already found applications in graphene, a carbon layer in which the electrons also move like massless particles. Now with this study of topological insulators, the general theory of relativity has made its debut in material physics as well.
The research was carried out by FOM employees Jan Dahlhaus, Chang-Yu
Hou and Anton Akhmerov, in the group of Carlo Beenakker at the Lorentz Institute of Leiden University. The researchers recently published their results in Physical Review B and these were discussed in Physics.
http://prb.aps.org/abstract/PRB/v82/i8/e085312
http://physics.aps.org/synopsis-for/10.1103/PhysRevB.82.085312?referer=rss
Contact
For further information please contact:
Prof. Carlo Beenakker, Lorentz Institute, Leiden University, telephone +31 (0)71 527 55 32.