Novel materials with 3D Dirac line nodes

Very recently materials that host a line node of Dirac cones, rather than a single Dirac point, have gained a lot of interest. In this talk I will talk about two materials hosting this unusual kind of electronic structure, Ca3P2 and ZrSiS. Ca3P2 was the first material that was predicted to host such a line node. Although it has been shown that the material can be synthesized, the growth of single crystals suitable for APRES measurements is challenging and experimental prove of the electronic structure is still lacking. I will here discuss the predicted band structure, as well as progress on the crystal growth. A different kind of 3D Dirac line node is observed in the material ZrSiS. In this case large single crystals were successfully grown and ARPES was used to confirm the electronic structure. This is the first time that such a line node was experimentally seen in any material. I will discuss the measured andcalculated electronic structure of ZrSiS and show that this compound is unique within the family of Dirac materials.