Abstract

Topology, a mathematical concept, became recently a hot topic in condensed matter physics and materials science. One important criteria for the identification of topological material is the band inversion and the crystal symmetry. In my talk I focus on new topological semimetals: Weyl semimetals. Binary phoshides are the ideal material class for a systematic study of Weyl physics. Weyl points, a new class of topological phases was also predicted in NbP, NbAs. TaP, MoP and WP2 . In NbP micro-wires we have observed the chiral anomaly but NbP has served also as a model system for astrophysics: realizing the gravitational anomaly in NbP and the hydrodynamic flow of electrons in WP2 . MoP and WP2 show exceptional properties such as high conductivity higher than copper, high mobilties and a high magneto-resistance effect. In magnetic materials, the Berry curvature measured via the classical anomalous Hall effect helps to identify interesting candidates for magnetic topological materials and devices.